Swimming Pool Hardware

[edwinchester]

Advice invited on sourcing a pool pump, sand filter and salt water chlorinator.

Would it be better to source from within Thailand or better to import from US or maybe Australia.

Are prices really that much more within Thailand and what issues such as import tax are there?

Thanks in advance Ed.

[WarpSpeed]

No they aren't they're relative. I'd buy from here locally you can get all the top US brands and the second tier Aussie brands. I would see about sourcing some of these from the states though.

You will pay more but they are well worth the extra cost. and they have a full range of available replacement internal parts so the likely hood of ever needing to remove and replace them is almost nil. Actually the Teflon seals are now guaranteed for life..

I used a supplier here in Bangkok some years ago to get mine but the name escapes me at the moment I'll have to search it if you're interested and they also supplied me with the pump and filter but I sourced my chlorinator elsewhere as I wasn't impressed with those offerings..

[edwinchester]

Hi warpspeed, thanks very much for your reply. I have been looking online at some of the Jandy products and they seem pretty good.

An email to the asia/pacific rep has so far not received an answer to my question of an official distributor here in Thailand so if you do know the name of your supplier I'd be most grateful. Ed.

[AllanB]

I have done a lot of research into pool equipment and there is, without doubt, a lot of BS flying around, from people trying to flog something new and expensive, or old and outdated. KISS, keep it simple stupid.

Sand filters are a waste of time space, PVC and money. Go for a simple, but good sized pump and matching inline cartridge filter, or bag filter, then keep your chlorine levels up using chlorine pellets.

I am currently building an infinity pool and am putting a huge (low cost) foam filter in the overflow trough, so the filration will be thorough and the pump load low. A friend of mine has been building pools in southern Spain for 12 years, where pools are extremely common and they use this "KISS" phylosophy there every time.

The biggest issue effecting water quality here in Thailand is "solar gain", this effects everything associated with the chemical balance, makes the pool uncomforatble to use and limits it's hours of use. So put a roof on it, enjoy the cooler water and save youself a lot of grief.

This summer I looked at about 40 pools in many different countries and without doubt the ones in Thailand had the worst water quality... by far. What does that tell you?

[Bagwain]

So many ex-perts here!!!!!

I have been involved with commercial and domestic swimming pools for over 15yrs in Oz, NZ & Thailand.

Sand filters with zeolite filters are the way to go,

Zeolite takes out organics and iron and magnesium. (problem all over Thailand)

Zeolite is 7 on the hardness scale and will last 5 + years (Sand is to soft in Thailand and last 12-18 mths at best)

Bags will not take out viruses and iron.

High chlorine is useless unless your water is in balance.

(Not many people seem to worry about this here in Thailand, hence so many illness caused by commercial pools)

Glad you are considering a salt chlorinator as it is the only way to go.

(We have found you have to keep the salt levels at over 4000ppm here though due to the humidity)

PM me if you want chat about this. (I am based in Pats but work all over Thailand)

ZEOLITE FILTRATION MEDIUM.pdf

Salt water chlorinator.pdf

[WarpSpeed]

Hi warpspeed, thanks very much for your reply. I have been looking online at some of the Jandy products and they seem pretty good.

An email to the asia/pacific rep has so far not received an answer to my question of an official distributor here in Thailand so if you do know the name of your supplier I'd be most grateful. Ed.

Sorry it took me so long to reply been running from floods and trying to save our house from inundation, we lost.. Anyways I'll send you a PM so as not to conflict with forum sponsors or others.

I should have mentioned in my first post that I used a Sta-rite Maxiglas pump and Hayward Star clear cartridge filter, the best combination, bar none..

[edwinchester]

Got the pm ws, much appreciated.

Hope you dry out and get back to normal soon.

Ed.

[WarpSpeed]

Got the pm ws, much appreciated.

Hope you dry out and get back to normal soon.

Ed.

I never was normal but thanks for the well wishes, good luck on your project..

[AllanB]

So many ex-perts here!!!!!

I have been involved with commercial and domestic swimming pools for over 15yrs in Oz, NZ & Thailand.

Sand filters with zeolite filters are the way to go,

Zeolite takes out organics and iron and magnesium. (problem all over Thailand)

Zeolite is 7 on the hardness scale and will last 5 + years (Sand is to soft in Thailand and last 12-18 mths at best)

Bags will not take out viruses and iron.

High chlorine is useless unless your water is in balance.

(Not many people seem to worry about this here in Thailand, hence so many illness caused by commercial pools)

Glad you are considering a salt chlorinator as it is the only way to go.

(We have found you have to keep the salt levels at over 4000ppm here though due to the humidity)

PM me if you want chat about this. (I am based in Pats but work all over Thailand)

ZEOLITE FILTRATION MEDIUM.pdf

Salt water chlorinator.pdf

Oh dear, more disinformation this time from a guy with "15 years experience".

1. Viruses removed by sand filters, who told you that? Viruses are killed not filtered out, killed in pools by chlorine. More relevent from a filtration point of view are parasites, such as crpytosporidium, resistant to chlorine and sand filters will not reove these, but a 1 micron bag filter will, some cartridge filters too. Then, in both cases they can be washed down the drain before they proliferate.

2. Sand filters have an indefinable, or varaible level of filtration since the sand is constantly moving, but at the very best down to 10 microns, however, often much larger particles pass through, bag filters are available down to 1 micron and anything below that is irrelevant, unless you want to drink copius quantities of pool water.

3. Iron particles (organics and minerals too) can be removed by any fine filter medium, bag, cartridge, or sand and the resulting iron bacteria killed by chlorine.

4. True, chlorine is less effective if the water balance is poor, but more important is water temperature and UV exposure, that is why a roof is so important. Nice to swim all day too without getting burned.

5. People get ill in commercail pools in Thailand because they are dirty and sweaty when they get in, they are cheap, so full of such people, they are full of kids who then P*ss in the water, adults too, The pools have insufficient funds and so low levels chlorine are used and the water temperature is too high for any chlorine left to have any effect. My guess is that at the end of a hot sunny, high UV day, when most Thais go swimming, what chlorine is left is doing Jack.

Go to the other end of the scale like Germany, mostly indoor pools, everyone showers before they go in and then walks throught a bleach bath on the way to the pool, plus eveyone wears a hat and is watched. You pays your money you takes your choice.

Bag filters are the future, no doubt in my mind.

[AllanB]

Mistake in my previous posting.

I stated that the best that could be achieved from a sand filter would be to remove particles down to 10 microns. However, this does not apply to low cost swimming pool filters as discussed on this forum and the correct figure should be down to 40 microns, making it by far the least effective of the 4 options available.

A 40 micron size particle is visible to the naked eye, not a problem until there are billions in the water, common bacteria found in pools range from 1 to 30 microns in size, meaning that all bacteria will pass through unabated.

It seems as though I am somewhat alone in pointing out these facts and opting for bag filters, but this is not so, my Kiwi friend has a pool from JD pools and he has a simple bag filter fitted to his skimmer box. Once a week he lifts out the filter bag and drops in the spare, 2 seconds and starts the pump again, he then spends a few minutes washing the old filter under the tap and puts it in the cupboard, what could be simpler? Water quality is fantastic.

So I would go for a bag filter any day and have.

[WarpSpeed]

So many ex-perts here!!!!!

I have been involved with commercial and domestic swimming pools for over 15yrs in Oz, NZ & Thailand.

Sand filters with zeolite filters are the way to go,

Zeolite takes out organics and iron and magnesium. (problem all over Thailand)

Zeolite is 7 on the hardness scale and will last 5 + years (Sand is to soft in Thailand and last 12-18 mths at best)

Bags will not take out viruses and iron.

High chlorine is useless unless your water is in balance.

(Not many people seem to worry about this here in Thailand, hence so many illness caused by commercial pools)

Glad you are considering a salt chlorinator as it is the only way to go.

(We have found you have to keep the salt levels at over 4000ppm here though due to the humidity)

PM me if you want chat about this. (I am based in Pats but work all over Thailand)

ZEOLITE FILTRATION MEDIUM.pdf

Salt water chlorinator.pdf

Oh dear, more disinformation this time from a guy with "15 years experience".

1. Viruses removed by sand filters, who told you that? Viruses are killed not filtered out, killed in pools by chlorine. More relevent from a filtration point of view are parasites, such as crpytosporidium, resistant to chlorine and sand filters will not reove these, but a 1 micron bag filter will, some cartridge filters too. Then, in both cases they can be washed down the drain before they proliferate.

2. Sand filters have an indefinable, or varaible level of filtration since the sand is constantly moving, but at the very best down to 10 microns, however, often much larger particles pass through, bag filters are available down to 1 micron and anything below that is irrelevant, unless you want to drink copius quantities of pool water.

3. Iron particles (organics and minerals too) can be removed by any fine filter medium, bag, cartridge, or sand and the resulting iron bacteria killed by chlorine.

4. True, chlorine is less effective if the water balance is poor, but more important is water temperature and UV exposure, that is why a roof is so important. Nice to swim all day too without getting burned.

5. People get ill in commercail pools in Thailand because they are dirty and sweaty when they get in, they are cheap, so full of such people, they are full of kids who then P*ss in the water, adults too, The pools have insufficient funds and so low levels chlorine are used and the water temperature is too high for any chlorine left to have any effect. My guess is that at the end of a hot sunny, high UV day, when most Thais go swimming, what chlorine is left is doing Jack.

Go to the other end of the scale like Germany, mostly indoor pools, everyone showers before they go in and then walks throught a bleach bath on the way to the pool, plus eveyone wears a hat and is watched. You pays your money you takes your choice.

Bag filters are the future, no doubt in my mind.

Iron bacteria??? Eh??

Disagree with the covered pools analogy except where the idea of no sun burn is concerned as UV rays provide a very valuable sanitizing source and work in concert with the Cl2. It's just important to control the Cl2 release and water balance to get the best result and that's where they fall short here and many other locales too.

JFYI not to be confrontational but bag filters are very old technology, they were first used many moons ago (read decades) when pools first arrived they are just now getting around to Thailand because they are simple but there are much more effective filters available now but maybe for Thailand they have a place where the pool care is not so sophisticated.

[fdimike]

I've been using 2 Hayward DE (diatomaceous earth) filters on my large 175,000L pool here in Udon Thani for about 6 years. These filters are extremely easy to use and will filter out particles as small as around 5 microns (better than either sand or cartidge) which is more than adequate for a swimming pool with correctly balanced water. I backwash the filters about once a year and have only taken them apart for a full cleaning once during the past 6 years. DE powder is widely available and very easy to add to the filter after backwashing.

[Naam]

conclusion: let'ts all agree to disagree.

[katabeachbum]

I've been using 2 Hayward DE (diatomaceous earth) filters on my large 175,000L pool here in Udon Thani for about 6 years. These filters are extremely easy to use and will filter out particles as small as around 5 microns (better than either sand or cartidge) which is more than adequate for a swimming pool with correctly balanced water. I backwash the filters about once a year and have only taken them apart for a full cleaning once during the past 6 years. DE powder is widely available and very easy to add to the filter after backwashing.

If I where to replace my sandfilters or cartridge filters, of which I prefere sandfilters, it would be with DE

and chlorinators have so far been the most expensive and complicated bacteria treatment i have experienced. Th fluctating voltage provides short lifetime. Back to Chlorine tablets when they die, simple and inexpensive

[WarpSpeed]

I've been using 2 Hayward DE (diatomaceous earth) filters on my large 175,000L pool here in Udon Thani for about 6 years. These filters are extremely easy to use and will filter out particles as small as around 5 microns (better than either sand or cartidge) which is more than adequate for a swimming pool with correctly balanced water. I backwash the filters about once a year and have only taken them apart for a full cleaning once during the past 6 years. DE powder is widely available and very easy to add to the filter after backwashing.

All true Mike but actually DE filters filter to within 1 micron so even more efficient..

[WarpSpeed]

I've been using 2 Hayward DE (diatomaceous earth) filters on my large 175,000L pool here in Udon Thani for about 6 years. These filters are extremely easy to use and will filter out particles as small as around 5 microns (better than either sand or cartidge) which is more than adequate for a swimming pool with correctly balanced water. I backwash the filters about once a year and have only taken them apart for a full cleaning once during the past 6 years. DE powder is widely available and very easy to add to the filter after backwashing.

If I where to replace my sandfilters or cartridge filters, of which I prefere sandfilters, it would be with DE

and chlorinators have so far been the most expensive and complicated bacteria treatment i have experienced. Th fluctating voltage provides short lifetime. Back to Chlorine tablets when they die, simple and inexpensive

There's draw backs to all sanitizing systems and I agree a salt chlorinator is touted as hands off but realistically it isn't especially once it ages a couple of years when it just begins to pay for itself. It is in effect also a small hydrogen bomb in your pool room but they don't often inform you of that in the sales brochure.

But tablets are by far one of the worst ways to sanitize as they rapidly raise your dissolved solids (solids dissolving I.E. a tablet) which are the catalyst for future problems with algae growth and also reduce your T/A and Ph to cause other potential balance problems, equipment and pool surface damage especially if used in the skimmer and not free floating around the pool while raising your Ca levels.

For example I've even seen pools where the customer didn't want a free floating chlorinator and they tied it to the stainless ladder in front of a return (which like the skimmer dissolves them prematurely they're supposed to be more time released) but in essence the tablets ruined their ladder with corrosion and also eroded down to the bare concrete and severely discolored the wall in a distinct pattern that demonstrated the flow of the return in a fan pattern that emanated away from it's origin, it also ruined all of the water line tiles by removing the glazing in that location as well and softened and removed all the tile grout down the entire length of the pool.

Most companies back in the states in the up to date regions such as Florida and Ca have long since stopped using tabs for daily chlorinating and only in extreme cases where supplement Cl2 is required to support the pool over the week as they cause more problems then they solve.

Bottom line, where pool sanitizing is concerned the old fashioned labor intensive way of adding liquid Cl2 and muriatic acid directly and manually is still the best way but here where the chems are inconsistent in content and hard to acquire a salt CL2 machine has to be the best option.

[fdimike]

Kata

I don't have problems with electricity up this way. If I did I would handle it one of two ways. I would first visit the electric company to ask them if there are sufficient transformers in your area to handle the load. That would probably entail a long hard battle. In the interim you can install a large whole house capacitor which will help smoothe out the electrical ups and downs. You can also install 3 phase power.

Hope this helps a bit.

[fdimike]

Warp

I thought they filtered down to 5 microns. 1 is even better

[AllanB]

So many ex-perts here!!!!!

I have been involved with commercial and domestic swimming pools for over 15yrs in Oz, NZ & Thailand.

Sand filters with zeolite filters are the way to go,

Zeolite takes out organics and iron and magnesium. (problem all over Thailand)

Zeolite is 7 on the hardness scale and will last 5 + years (Sand is to soft in Thailand and last 12-18 mths at best)

Bags will not take out viruses and iron.

High chlorine is useless unless your water is in balance.

(Not many people seem to worry about this here in Thailand, hence so many illness caused by commercial pools)

Glad you are considering a salt chlorinator as it is the only way to go.

(We have found you have to keep the salt levels at over 4000ppm here though due to the humidity)

PM me if you want chat about this. (I am based in Pats but work all over Thailand)

ZEOLITE FILTRATION MEDIUM.pdf

Salt water chlorinator.pdf

Oh dear, more disinformation this time from a guy with "15 years experience".

1. Viruses removed by sand filters, who told you that? Viruses are killed not filtered out, killed in pools by chlorine. More relevent from a filtration point of view are parasites, such as crpytosporidium, resistant to chlorine and sand filters will not reove these, but a 1 micron bag filter will, some cartridge filters too. Then, in both cases they can be washed down the drain before they proliferate.

2. Sand filters have an indefinable, or varaible level of filtration since the sand is constantly moving, but at the very best down to 10 microns, however, often much larger particles pass through, bag filters are available down to 1 micron and anything below that is irrelevant, unless you want to drink copius quantities of pool water.

3. Iron particles (organics and minerals too) can be removed by any fine filter medium, bag, cartridge, or sand and the resulting iron bacteria killed by chlorine.

4. True, chlorine is less effective if the water balance is poor, but more important is water temperature and UV exposure, that is why a roof is so important. Nice to swim all day too without getting burned.

5. People get ill in commercail pools in Thailand because they are dirty and sweaty when they get in, they are cheap, so full of such people, they are full of kids who then P*ss in the water, adults too, The pools have insufficient funds and so low levels chlorine are used and the water temperature is too high for any chlorine left to have any effect. My guess is that at the end of a hot sunny, high UV day, when most Thais go swimming, what chlorine is left is doing Jack.

Go to the other end of the scale like Germany, mostly indoor pools, everyone showers before they go in and then walks throught a bleach bath on the way to the pool, plus eveyone wears a hat and is watched. You pays your money you takes your choice.

Bag filters are the future, no doubt in my mind.

Iron bacteria??? Eh??

Disagree with the covered pools analogy except where the idea of no sun burn is concerned as UV rays provide a very valuable sanitizing source and work in concert with the Cl2. It's just important to control the Cl2 release and water balance to get the best result and that's where they fall short here and many other locales too.

JFYI not to be confrontational but bag filters are very old technology, they were first used many moons ago (read decades) when pools first arrived they are just now getting around to Thailand because they are simple but there are much more effective filters available now but maybe for Thailand they have a place where the pool care is not so sophisticated.

Today was quite warm up here, at around 40c in the sun, so at around 2pm we all fancied a cool swim and it was divine,all because of my very simple steel roof. The only disadvantage was that is messed up our game of volley-ball.

I am not sure how valid (to what extent) your comment is about the positive effects of UV and my pool is not 100% covered 100% of the day, but I suspect the much lower temperature of the water must more than offset that, by maintaining the effectiveness of the chlorine. Plus direct sunlight promotes the growth of algae, so I am perhaps avoiding a host of other problems too.

My own personal opinion is that in the tropics, a pool roof is the best thing since sliced bead and I can enjoy my pool while everyone else is sweltering and waiting for nightfall.

Of course bag technology isn't new, but that is true for everything else used and the only filters that compete on a particle removal level are DE filters. Correct me if I am wrong but I think they can only be used as a secondary filter, as they would become clogged too easily?

They are certainly much cheaper than the commonly used sand filter, they clean to a know level, whereas sand filters don't. You can see and clean them long before they become clogged, can clean them properly and even sanitise them too, all very quickly.

Another advantage is that if you have something you wish to remove, like calcium particles (from chlorine tablets), suspected parasites, just change the bag pore size and take them out. There is also something called "slime bag", which fits over the supply jet opening/s, though I haven't tried one (hope I never need to), the theory seems sound.

I think there are people everywhere in the world who don't maintain their pool water, so I think that the unsophisticated, or KISS, is quite a good answer. If you assume your customers are stupid, forgetful, or lazy, you won't be disappointed. We have 4 pools in our village (all1.5m baht+) and mine is the only one in use, by humans,

I would conclude by saying that I am not selling anything here, I hope I am bringing some fresh ideas to this forum, since my pool is different in most respects to the typical Thai pool. I have the utmost respect for those who argue on the basis of fact, logic and common sense. less so for those who are simply on an ego trip.

[WarpSpeed]

My own personal opinion is that in the tropics, a pool roof is the best thing since sliced bead and I can enjoy my pool while everyone else is sweltering and waiting for nightfall.

Curious what tropics have you spent any significant time in prior to your relocation to Thailand and how many pools did that involve? Actually a screen enclosure is the best thing since sliced bread as it reduces temps and prevents most debris as well as allowing some filtered sunlight in, not to mention the comfort from insects while sitting by your pool side..

Of course bag technology isn't new, but that is true for everything else used and the only filters that compete on a particle removal level are DE filters. Correct me if I am wrong but I think they can only be used as a secondary filter, as they would become clogged too easily?

Which filters are secondary? DE or bag filters? Bag filters are nothing more then secondary at best but would do well in concert with a sand filter but even in that context is just more work when the modern filters are plenty efficient enough. The fact that you ask that question though is pointing towards a lack of complete understanding though I don't mind informing you as long as that's what it is..

When I say "not new technology" I mean so old it's long been forgotten (by informed swimming pool maintenance professionals and contractors) and replaced by all of the current types of filter media such as cartridge, DE and even sand though sand has had a bit of staying power predating most of the others and as ancient as bag filters.

[Naam]

My own personal opinion is that in the tropics, a pool roof is the best thing since sliced bead and I can enjoy my pool while everyone else is sweltering and waiting for nightfall.

Curious what tropics have you spent any significant time in prior to your relocation to Thailand and how many pools did that involve? Actually a screen enclosure is the best thing since sliced bread as it reduces temps and prevents most debris as well as allowing some filtered sunlight in, not to mention the comfort from insects while sitting by your pool side..

some people like roofs, others like screens. some think that cold pool water is "divine", others prefer 28-29ºC and are heating their pools. and then there are the misfits (e.g. the Naams and their dogs) who don't tell other people how to build their pools but are quite happy with their -not so divine- completely enclosed, airconditioned and ventilated pool area which is free of debris, dirt and insects.

[WarpSpeed]

My own personal opinion is that in the tropics, a pool roof is the best thing since sliced bead and I can enjoy my pool while everyone else is sweltering and waiting for nightfall.

Curious what tropics have you spent any significant time in prior to your relocation to Thailand and how many pools did that involve? Actually a screen enclosure is the best thing since sliced bread as it reduces temps and prevents most debris as well as allowing some filtered sunlight in, not to mention the comfort from insects while sitting by your pool side..

some people like roofs, others like screens. some think that cold pool water is "divine", others prefer 28-29ºC and are heating their pools. and then there are the misfits (e.g. the Naams and their dogs) who don't tell other people how to build their pools but are quite happy with their -not so divine- completely enclosed, airconditioned and ventilated pool area which is free of debris, dirt and insects.

A/C? You must be Yerman??

For my part I don't tell people how to build their pools but good advice based on a broad range of real world experience is always in good order and not conjecture or simple personal preference except if that personal preference is again based on numbers of examples and not just one or 2, that's the job of a good contractor, to share their experience in order to aid in an informed decision..

[katabeachbum]

My own personal opinion is that in the tropics, a pool roof is the best thing since sliced bead and I can enjoy my pool while everyone else is sweltering and waiting for nightfall.

Curious what tropics have you spent any significant time in prior to your relocation to Thailand and how many pools did that involve? Actually a screen enclosure is the best thing since sliced bread as it reduces temps and prevents most debris as well as allowing some filtered sunlight in, not to mention the comfort from insects while sitting by your pool side..

some people like roofs, others like screens. some think that cold pool water is "divine", others prefer 28-29ºC and are heating their pools. and then there are the misfits (e.g. the Naams and their dogs) who don't tell other people how to build their pools but are quite happy with their -not so divine- completely enclosed, airconditioned and ventilated pool area which is free of debris, dirt and insects.

each to their own, I would miss the sun, the moon, the stars, the view and the sound of nature

[Naam]

A/C? You must be Yerman??

Ladies und Tchentelmen... vee haff a vinner

p.s. the posted picture is a few years old. our pool area is now "fully furnished" and used quite often as an alternate living/family room.

I would miss the sun, the moon, the stars, the view and the sound of nature

after having spent more than half of our lives in tropical environments we hate the sun. however, a 42m² glass front towards our garden lets us see the moon and the stars (if no cloud cover) and hear the sound of nature, unfortunately only the frogs in our pond and/or our dogs when they chase a cat.

[AllanB]

I have been in Thailand for 4 years, 2 part time and the last 2 permanently. The summer before last I dived into Khonkaen University's big pool and I barely made it to the other side, the water was so hot. It was such an unpleasant experience I never went back. Last summer a friend of mine built a pool with a roof and side screens and the water temperature was very pleasant and we spent the whole day in and out his pool.

That is the reason I put one on mine, so I don't need 20 years of experience in the tropics to convince me of the value of a roof. Okay the water is a little cold for some at 26-27c and a heater could solve that, but the roof comes into it's own when the summer arrives. Plus nobody can deny the value of the improved sanitation a roof provides, oh! I should have said that........

Now this business on bag filters, some of you guys obviously need informing....

.

A bag filter is a single filter available in a range of pore sizes, which in my case sits in my trough and takes out all particles down to it's pore size. I run a 50 micron filter, which is equal to the theoretical level of a sand filter. So why would it need an additional sand filter?

If I want to improved my level of filtration, I simply change the bag and choose one with a smaller pore size, (down to 1 micron) so it is still a primary filter. The downside of doing this is that it gets clogged quicker, so is only used on a temporary basis, if I have a problem.

The origins, age and history of "bag filters" are all irrelevant, it works, end of story.

You seemed to be implying that a DE filter is a primary filter, whereas all the DE filters I have seen, are installed down-steam of a sand filter, making it a secondary filter That is why I questioned it and I personally cannot see how it would work any other way.

[WarpSpeed]

I have been in Thailand for 4 years, 2 part time and the last 2 permanently. The summer before last I dived into Khonkaen University's big pool and I barely made it to the other side, the water was so hot. It was such an unpleasant experience I never went back. Last summer a friend of mine built a pool with a roof and side screens and the water temperature was very pleasant and we spent the whole day in and out his pool.

That is the reason I put one on mine, so I don't need 20 years of experience in the tropics to convince me of the value of a roof. Okay the water is a little cold for some at 26-27c and a heater could solve that, but the roof comes into it's own when the summer arrives. Plus nobody can deny the value of the improved sanitation a roof provides, oh! I should have said that........

Now this business on bag filters, some of you guys obviously need informing....

.

A bag filter is a single filter available in a range of pore sizes, which in my case sits in my trough and takes out all particles down to it's pore size. I run a 50 micron filter, which is equal to the theoretical level of a sand filter. So why would it need an additional sand filter?

If I want to improved my level of filtration, I simply change the bag and choose one with a smaller pore size, (down to 1 micron) so it is still a primary filter. The downside of doing this is that it gets clogged quicker, so is only used on a temporary basis, if I have a problem.

The origins, age and history of "bag filters" are all irrelevant, it works, end of story.

You seemed to be implying that a DE filter is a primary filter, whereas all the DE filters I have seen, are installed down-steam of a sand filter, making it a secondary filter That is why I questioned it and I personally cannot see how it would work any other way.

[Naam]

You seemed to be implying that a DE filter is a primary filter, whereas all the DE filters I have seen, are installed down-steam of a sand filter, making it a secondary filter That is why I questioned it and I personally cannot see how it would work any other way.

i'm not sure who implied that but all the "zillion" pools i have seen in Europe and the USA had only DE filters as primary filters. any sand filter or bag filter would have been considered as stone age technology

[AllanB]

You seemed to be implying that a DE filter is a primary filter, whereas all the DE filters I have seen, are installed down-steam of a sand filter, making it a secondary filter That is why I questioned it and I personally cannot see how it would work any other way.

i'm not sure who implied that but all the "zillion" pools i have seen in Europe and the USA had only DE filters as primary filters. any sand filter or bag filter would have been considered as stone age technology

I haven't seen only one pool with a DE filter, but as a secondary and although that was quite small it was very expensive, the primary version of a low micron DE would presumably have to be quite large and quite expensive.

I keep hearing all this stuff about "old" versus "new technology", you should realise that bag filter materials have changed a lot over the years, like everything else. These new materials give them a wide range of mechanical properties and they are currently used extensively in numerous industries, including water treatment. I am still waiting for a real reason for not using them and so far everyone is avoiding that.

I have given my reasons for choosing them over other methods, all of which are technically valid, please be kind enough to do the same.

[Naam]

I keep hearing all this stuff about "old" versus "new technology", you should realise that bag filter materials have changed a lot over the years, like everything else. These new materials give them a wide range of mechanical properties and they are currently used extensively in numerous industries, including water treatment. I am still waiting for a real reason for not using them and so far everyone is avoiding that.

I have given my reasons for choosing them over other methods, all of which are technically valid, please be kind enough to do the same.

there's one thing missing in your arguments. if i'm not mistaken you are living somewhere up north or north-east where the ambient temperature in "winter" is much cooler then down south. moreover, correct me if i'm wrong, you mentioned operating your pool since six weeks, id est the coolest time of the year. let's wait another 2 or 3 months and then repeat your claim that 1 hour filtering time is sufficient for your pool.

the primary version of a low micron DE would presumably have to be quite large and quite expensive.

that is correct. i don't remember how much my last DE filter was (bought in 1994) but the size was not bigger than the average sand filter used in Thailand.

[Naam]

filter media

here in Thailand i initially used a sand filter but was not happy because it took ages to remove some flocculant. then i experimented and added once in a while 2 pounds of DE on top of the sand and backwashed after 8-10 pumping hours. result: much better.

since several months i am using zeolite as filter media because some pool gurus in Thaivisa recommended it. stupid me had no idea that zeolite had to be washed/rinsed initially before using. result: pool water looked like watery milk. no change even after 20-25 hours pump running time, zeolite was not able to filter out it's own "dust". two pounds of added DE and 12 hours filtering did the trick and the water was again crystal clear.