Koi Carp info thread

[krayner]

I wanted to know about keeping koi carp in Thailand, like how well do they do in the hot weather, will I need to shade the pond, how deep does a pond need to be.

Is the 115mm Thai soil pipe strong enough to take the weight of several feet of water. I assume that it is since it would have to be buried anyway.

The only reason that I ask is that when I looked at some in shop it struck me as being on the thin side, not as thick as the UK.

Talking to a uk supplier about buying some bottom drains to take out to Thailand, he commented that I should be careful if the wall thickness is not great, that once buried in the bottom of a pond under a few feet of water that it might not take the load.

[bkkmadness]

though pond fish is not really my speciality I would say Koi will have no problems out here in the higher temp, and carp are very adaptable.

I would have said in the UK about 3-4 feet deep for a Koi Carp pond, but out here I would be inclined to add a little more to that, maybe 5 feet deep as the water will stay cooler at the bottom i would have thought. Some part of he pond shaded would be a very good idea not just for the temp but to inhibit algae growth. I'd say in these hotter temps good water circulation is the key to sucess.

[tuky]

though pond fish is not really my speciality I would say Koi will have no problems out here in the higher temp, and carp are very adaptable.

I would have said in the UK about 3-4 feet deep for a Koi Carp pond, but out here I would be inclined to add a little more to that, maybe 5 feet deep as the water will stay cooler at the bottom i would have thought.  Some part of he pond shaded would be a very good idea not just for the temp but to inhibit algae growth.  I'd say in these hotter temps good water circulation is the key to sucess.

<{POST_SNAPBACK}>

We have 5 in 3 feet of pond and they seem happy even in full sun, although the water itself needs to be changed often as it turns green fairly quickly. We also have a waterfall circulating the water.

[bkkmadness]

Though it's harder to stop the problem of green water of you pond is in full sun, it's worth remembering that another major factor that contributes to green water in a pond is the level of Nitrate that builds up.

Nitrate comes from the fish waste after the filter breaks it down from ammonia and hard to avoid in a pond.

If you add a lot of fast growing plants to your pond, you may be able to reduce this nitrate level significantly as the plants feed on it, eventually starving out the green algae that gives you the green water.

It's certainly a natural solution worth trying, unless you want to pay out for a UV light filteration system on the pond. Koi Carp will eat a lot of the plants in the pond, so if you use anything, I suggest you make sure they are fast growing plants, maybe Elodea if you can get it out here.

Not every pond can acheive the correct balance though, it's harder if you have more fish in your pond for a start.

When building the pond bear in mind Koi can grow quickly and to quite a size, so make sure there's plenty of room for them if you intend to keep them for a while.

BTW, I'm really envious of you, I miss my pond at the family house back in the UK, got some great Koi and other fish in there.

[aughie]

In the US they use schedule 40 pvc pipe on smaller ponds. Schedule 120 is the thin stuff used for underground lawn sprinkling systems. I don't know how they guage pvc pipe in LOS. For koi the pond should be at least 3 feet deep to discourage algae growth, to maintain cooler water, and to allow the koi to retire if they wish. Perhaps e-mail this person.

http://thailand4life.net/smithgarden/

Edited April 26, 2005 by aughie

[bkkmadness]

Great link Aughie, that guy certainly has got a great garden and pond.

[aughie]

I agree with a backyard like his i wouldn't be missig the beach. I'd be very content steping out on the patio. My guess is the color of the pipe in the pic designates it's qualifications.

[stevemarkwell]

I've built and maintained a lot of ponds, and kept koi quite a bit over the years in both hot and cool climates. Koi are well-adapted to colder water, able to maintain an almost dormant state at near-freezing temperatures. However their metabolisms function at full capacity in 25 degree water. They are going to eat more, grow faster, and produce more waste, which will initially show up as ammonia in your pond. Ammonia is of course highly toxic, so you need good biological filtration to convert it into nitrite, then to nitrate, which is relatively harmless in and of itself, and can be removed by the bacteria that colonize the roots of plants. As was stated earlier, high nitrate will also cause algal bloom, and it can also cause aerobic bacterial blloms, which are especially dangerous to fish because such events starve the water of oxygen.

To counteract and prevent the effects of too much nitrate in your pond, I recommend a few things: first, when in doubt, make your filtration system too big. You can't have too much biological filtration, and what's nice is that you can build your own system very easily. I've used volcanic rock, crushed concrete, cynder blocks, gravel, terra cotta pot shards, and several other types of materials; the goal is to have as much surface area as possible for the bacteria to colonize, so if using stone, use something porous. Start with the larger media, and work your way down to the smaller, and make sure that whatever setup you use, it is easy to remove the media for routine cleaning. The 'muck' you remove can be added to your compost heap for use in the rest of your garden. Remember that many of the bacteria that convert ammonia and nitrite are killed by ultraviolet radiation, so your biological filter needs to be as dark as possible.

Next, I recommend a plant filter; this is created by routing the water from your pond through a channel containing densely packed floating plants; I would try to stick to native species if possible, as invasive plants of this type are a major ecological problem worldwide. The channel is best placed before the biological filtration system, or as a completely separate feature, and can be made 1 meter wide by half a meter deep, or if you prefer, 3 feet by 1 and a half. You will then add dividing partitions, which can be walls that run 2 and a half feet across the channel, alternating sides each time; this will prevent the plants from all drifting to the far end of the channel. You can also build the partitions all the way across, creating an opening at the bottom of each one for water to pass through, or you can place them at sharper angles. You can also create a shallow shelf along the edge of this channel, to contain bog plants. Again, I recommend native species, or species from the region in general that aren't going to naturalize. There is a beautiful palm called a sealing wax palm that can be grown in six inches of water; it has bright red leaf stalks, and grows slowly to 30 feet. (I'm slipping back into feet; it's hard to get used to the metric system.) The advantage to plants like these is that they cannot be eaten by koi, as most of the plant is above the water line, and what is below it is tough root tissue.

A large drain, 4 to 6 inches in diameter, in the lowest point of your pond will enable you to remove the buildup of organic matter at the bottom of the pond. This doesn't need to be connected to your filtration system; the drain pipe can simply go through a ball valve that you open every so often to let the muck drain out. This is only possible if you have an area on your property that is lower in elevation than the lowest point of your pond, but if you can design your pond this way, it will make cleaning it easier. If you position a net of some kind at the end of the pipe while draining it, you can capture the organic matter while letting the water drain through. Also, the fewer joints and and elbows in the pipe the better, so the material will not be trapped inside and clog your drain pipe. I would follow the advice of the other contributors to this thread with regard to your drain pipes -- the thicker the better.

A waterfall or stream, placed after your biological filter, will provide two benefits: first, it will give you more biological filtration, but more importantly, it will agitate the surface of the water, saturating it with breathable oxygen. Some people like aerators or venturis, but I prefer to rely on surface agitation; it looks more natural, and makes a very relaxing sound.

Snails -- find some aquatic snails (make sure they are algae-eaters and not carnivorous) and put them in your pond. You only need one, really, because snails can reproduce asexually if they need to. A healthy snail population will control any algae problems. Use native snails though. There is also a native fish often called a Chinese algae eater which will feed on the algae in your pond.

For depth, keep in mind that koi are bottom feeders, and in a very deep pond you will only see them at feeding time, when they come to the top for a handout. Rather than try to make the pond especially deep, I would focus on providing a few shaded areas throughout the day, and some good hiding places, but keep your pond shallow so that you can see your fish whenever you want to. They will eventually stop hiding from you in the hiding places you provide, using them only to escape potential predators that visit your garden. The purpose of deep ponds, such as those built in the UK and in the colder parts of the US, is not to provide cooler water for your fish during warm weather, but rather to provide warmer water for your fish during extreme cold, which obviously is not an issue in Thailand. When water reaches 4 degrees C an inversion takes place, and the colder water rises to the top, while the warmer water sinks; this is why the ice forms at the top of the pond, and not at the bottom, and why a deep pond is of benefit in colder climates. Studies have been conducted in this subject, and it has been shown that deep water is of no real benefit to koi in warm climates. Shallow water will also be an advantage if you are planting water lillies, as the lilly pads will reach the surface of your pond sooner, generating more new growth and more blooms; reaching the top faster also means less opportunity for your fish to eat the new growth.

Perhaps the most important thing to remember is to go easy on the number of fish you put into your pond. The less fish you keep, the less waste you will have to remove, and the more effective your filtration system will be. You can always add more later.

Sorry if this post is too long and has a bunch of info you were already aware of. I tend to overdo it a bit when it's a topic I'm really into.

[bkkmadness]

An excellent post. Vegetation filter is a great idea, especially in a Koi Pond as they might well eat a lot of plants in the pond if they cannot grow fast enough.

Although Biological filteration is the most important thing in the pond for keeping fish, I think I'm correct in saying it only promotes the growth of aerobic bacteria which breaks down ammonia and nitrite but will not help much in the way of breaking down nitrate which need anaerobic bacteria to break it down. Plants are definately the best way of getting rid of nitrate in the pond.

Gravel can get easily clogged up in a biolgical filter and be a pain to clean if it is too fine a grain. I recommend something along the lines of small pieces of plastic tubing that you will see in the filters in fish tanks here. Easy to clean, allow easy water flow and a large surface area. Plus cheap to buy in large quanities.

I have to still say I would go with the deeper pond in this weather as relaxed Koi though being bottom feeders will often stay near the top of the pond especially when you go to look into the pond as they will rise to the surface thinking you are about to feed them. Koi that are fed from floating pellets will stay near the top of the pond on the constant look out for food I found in my own pond back in the UK.

Also, concerning the shallow shelfs it's worth noting a problem that sometimes occurs in the UK with Herons. Herons use shallow shelfs in ponds to wade into the water before eating your fish, if you don't have these shallow shelfs then perhaps this is a problem that could be avoided. Of course, I don't know how bad the Heron situation is in Thailand or where you are living.

Another great algae eater is the Plecostomus fish, which though is South American can be found out here easily and will eat lots of algae from the sides of the pond. The algae at the side of the pond is never so much the problem as the single celled algae which gives you the green water problem in the pond.

Sorry if this post is too long and has a bunch of info you were already aware of. I tend to overdo it a bit when it's a topic I'm really into.

I tend to waffle on about anything fish related too!

Edited May 2, 2005 by bkkmadness

[Ajarn]

Great info here. Thanks!

I also have a couple of fish ponds, both with waterfalls for filtering and cleaning (though I never new all the details about 'how' until now!), and the fish seem quite happy.

I currently have a problem, though. My garden has a few big Mango trees, and they excerete some kind of slightly oily substance that quickly turns black... When the first hard rains hit, a lot of the mango gunk ended up in the ponds and the waterfall. All the rocks with flowing water have turned black, and the water no longer is being cleaned by the plants (also gunked-up) or the rocks the water flows over.

Because I can't remove many of the plants or rocks, any thoughts on the best way to get rid of this gunk? My only idea is to remove the fish, drain everything, and just get in there with a scrub brush on eveything... Are there any chemicals that might help to disolve this grunge without leaving any harmfull effects to my fish (koi and other mixed 'soi fish') ?

My house keeper and gardener will be in there doing the dirty work, so I'd like to learn the most effective and efficient ways to clean this mess, to minimize headaches for them and, subsequently, for me, too.

Any advice is appreciated.

Edited May 2, 2005 by Ajarn

[tuky]

Sorry if this post is too long and has a bunch of info you were already aware of.  I tend to overdo it a bit when it's a topic I'm really into.

<{POST_SNAPBACK}>

Hi Steve, great info.

At the moment we only have a straight pump system to push the water to the top of the waterfall, then on down back into the pond. Is there any chance you could perhaps draw a scmematic type of drawing to allow me to understand the process a little better? I worry about our fish, one has died already.

We have one lily pad plant in there and that is all.

Cheers

This it, mind you it has been landscaped and looks a lot nicer now.

Edited May 2, 2005 by tukyleith

[bkkmadness]

If you have the pump already then your've only got to add a box filter to the side of the pond Tuky, or perhaps some kind of small filter box inside the pond would work, but personally I find box filters a lot easier, more effective and convenient to use. Shouldn't cost you much either as the pump is the pricey bit. Saying that this is going from old UK costs I know it's all pretty cheap out here.

At the moment your pump is just oxygenating the water, but lack of oxygen in a pond is not the main cause of fish deaths, it's the toxins from the fish waste.

What size is your pond in feet Tuky? Length/width/depth so can work out your gallonage. Do you know what your pump turns over Gallons/per hour? As far as I recall you should be turning over at least half the ponds gallonage per hour through your filter on a well stocked pond. Whats the pump name and number? This usually helps finding out info the GPH.

Don't know how to draw you any kind of diagram for the filter but put pretty simply it works like this on a simple system.

The pump sends water straight out of the pond to a box on the side of the pond, where it pumps in water through a spray bar at the top of the filter tank.

The water thens runs through a few layers of foam which is the mechanical side of your filter and takes the bigger bits of crap out of the pond. After passing through the foam the water comes to the bottom chamber (the biological filter) which is full of plastic tubing/gravel or some kind of media which has a large surface area where aerobic bacteria builds up. This bacteria breaks down the poisons (ammonia/nitrite from your fish waste and converts it to the less harmful to fish(unless in huge amounts) to the algae loving nitrate).

In 9/10 cases the build up of one of these toxins that cause fish to die in ponds and tanks alike if there seems to be no disease present. After passing through the bacteria/biological section of the filter the water then runs out back into your pond, via an outlet tube which should be a larger bore than your inlet tube to prevent your filter box flooding.

To add a vegetation filter to this you simply have the water running back into another 'open air' water chamber filled with plants first before going back into your pond. The plants will remove the nitrate. Though you do not always need a vegetation filter set up, often a lot of plants in the pond will do. People tend to use vegeation filters if they do not or cannot have plants in the pond.

It's quite easy to hide all the filters into a decorative waterfall feature. I know my description was a bit crap, but I will try to find you some kind of diagram on the net Tuky.

Ajarn, Been thinking on your problem and I reckon you may need to get in there and scrub the rocks and literally take it all out by hand. I wouldn't trust any chemical in there that could get rid of organic waste from mangos that would not adversly effect your fish and plants. Perhaps Steve knows better?

I wouldn't drain the whole pond though if possible and leave the water in the filter tanks otherwise your in serious danger of wiping out your biological filter.

And perhaps cut back those Mango trees, or net over part of the pond to prevent it happening in future?

Edited May 2, 2005 by bkkmadness

[bkkmadness]

Couldn't find any great filter diagrams Tuky, but here's something that may suit you if you have a small pond and don't want to get into it too much, it's just a diagram of a simple bucket filter which is a kind of in the pond filter which I mentioned.

bucket filter

Very simple to make a homemade one, it's just simply sitting your pump inisde a container filled with medium so that any water that gets pulled into your pump has to pass through a filter first.

I always prefer the filters on the outside of the pond myself and ponds always been large so needed them, but maybe this can serve you well?

And for Steve, on my travels through Google found this

[bkkmadness]

You just added that pic Tuky? I didn't notice it before.

Ok, looks like your wanting a waterfall set up, and you have some space behind that waterfall so I would think some kind of filter barrel might be in order, with water being pumped in at the bottom, filling the barrel up, with the water passing through biological filtering medium and mechanical filteration medium and then passing back through a pipe at the top onto your waterfall.

I don't know how the waterfall is set up but may be an idea as if you have a bottom to top flow filter it will be easier to hide behind the waterfall in your case I think.

[Nigelmartin]

Sorry if this post is too long and has a bunch of info you were already aware of.  I tend to overdo it a bit when it's a topic I'm really into.

<{POST_SNAPBACK}>

Hi Steve, great info.

At the moment we only have a straight pump system to push the water to the top of the waterfall, then on down back into the pond. Is there any chance you could perhaps draw a scmematic type of drawing to allow me to understand the process a little better? I worry about our fish, one has died already.

We have one lily pad plant in there and that is all.

Cheers

This it, mind you it has been landscaped and looks a lot nicer now.

<{POST_SNAPBACK}>

A useful web site is : www.koicymru.co.uk/construct.htm gives some useful tips on pond and filter design. Nigel

[bkkmadness]

Nigel, I cant get that link to work, can you check it?

[BrissyBoy]

Link doesn't work?

<{POST_SNAPBACK}>

There was an extra (.) in there.

this link should work

Guide to making Ponds

Hope this helps

[bkkmadness]

Brissyboy sorted out the link, it's here

Done, Mr Fishkeeper.

tukyleith

Edited May 2, 2005 by tukyleith

[aughie]

To add:

Live plants and algae will consume ammonia. Bacterial filtration is used to compete with the algae for available nutrients. If the water is nutrient poor due to substantial bacterial action algae cannot flourish.

Snails carry parasites like flukes. Flukes once introduced are tough to kill especially gill flukes. Snails can be introduced from eggs laid on livewater plants introduced to the pond. Detrius on the floor of the pond is a breeding ground for flukes. Copper sulfate can be used to kill parasites but the treatment can kill loaches which are a popular ornamental fish in SEA.

-a

[stevemarkwell]

I don't want to bicker, but plants definitely do not consume ammonia -- they can only take in nitrate. This is a well established scientific fact. High ammonia levels will not only kill your fish, they will kill your plants as well -- just look at the brown spots on the lawn left after your dog pees on it. Algae and multicellular plants are able to make use of nitrate, which is the finished product in the work done by nitrifying bacteria; these bacteria do not compete with algae for nutrients, they create nutrients that are useable by plants. The nitrifying bacteria found in biological filtration systems, around the roots of your plants, and on the walls of your pond, do not consume nitrate, and the plants and algae in your pond do not comsume ammonia or nitrite. There are two ways to remove nitrate from your pond, in order to help limit algae growth, and those are to make sure to have a lot of desireable plants in the pond, and to do frequent water changes. Even so, algae can convert raw sunlight into energy for growth and reproduction, and it can flourish in water that has additional nutrients, like phosphorus. That's why I like to have something in the pond that eats the algae, and use desireable plants, which do compete with algae for nutrients.

I've never had a problem with snails introducing parasites into my ponds, but it is certainly not unheard of; if you're concerned about this, use one of the algae-eating fishes mentioned in previous posts.

As for filtration, I've often made my own. There are so many different configurations that it's hard to know where to start, but if you know what the purpose of each component is, you can have a lot of success designing your own system. Then again, a commercially available filter is usually a pretty safe bet too. I prefer to make my own because I can typically create a much larger filtration system. I have certain preferences, which many people may disagree with for valid reasons, but I prefer to place the pump at the very end of the line, so that it is unlikely to be clogged by particles that will be removed from the water by the filter media. I like to have an easy way to remove said particles from filter and pond alike, which for me usually involves a sump and a large-diameter drain. And I like to use the most natural components I can, like porous stone for filter media, and live plants for removing nitrate, phosphorus, etc. I've had great success with homemade systems using rubbermade garbage cans, and have had crystal clear water for months at a time without doing water changes.

How you set up your filtration will also depend on the general scheme of your garden, elevation of your pond and the surrounding area, etc., so there's no one right way to do it. I would definitely look around online and check out some different how-to sites. I still consult these kinds of sources when designing ponds, even after years of building and maintaining them.

The thing with the mango trees has been baffling me all day. I'm stumped. Is the black material some kind of pitch? I don't know enough about that particular tree to give any advice. A scrub-down is probably in order, but you're going to lose a lot of beneficial bacteria; if you do it, make sure not to feed your fish for a while after they go back in the pond, and keep testing your water for ammonia and nitrite until both are minimal. I wonder if bacterial action will break down the black stuff over time, or if there is another biological solution that would be less drastic than draining the pond and scrubbing it out. I'll keep my eyes open for it.

How big are the trees? You may be able to move them. Even trees that seem too big to move can be taken out of the ground, their roots trimmed, and replanted in a more desireable location, but if they're huge, you'd need some pretty significant equipment to do the job, and it might not be worth your while.

[aughie]

You're right.

[bkkmadness]

A thread on the nitrogen cycle concerning fish, it's like a dream thread to me, I'm sure I should go back on the booze.

Yep, that mango tree thing had me stumped a bit too, if you can get the rocks out and scrub them and clear it out without removing all the water it'll definately be a bonus Ajarn.

One thing a fully established pond and biological filter should never need is a full water change, it upsets the whole balance, a partial water change is good enough, and with all the water evaporation you will get out here just topping it up occaisionally should be more than enough.

If memory serves, the stronger solutions for killing snails are generally copper based treatments and too much copper in the pond will be harmful to the fish as well. If you have a pond with plants there is no way you will not get snails in that pond. One of the best solutions that people use for getting rid of snails in tropical fish tanks can be used in ponds out here due to the warmer climate and that's by introducing Clown Loach - Botia Macracantha, they are readily available out here, can grow to about 8-12 inches and love eating snails.

I've always found the key to good fishkeeping is to be a little less reliant on chemical solutions for problems in ponds and find the natural way to deal with the problem.

Algae can be starved out with the right balance of plants. Algae can be eaten by certain fish. Snails can be eaten by certain fish.

A natural balance is what you should be constantly aiming for, and once you have it, unless something drastically changes within the enviroment of your pond, then you should be able to keep that balance maintained easily or rather, the balance will maintain itself.

Edited May 3, 2005 by bkkmadness

[stevemarkwell]

Good call on the clown loaches -- I used to sell them to people all the time on that point alone, but they also get to be pretty good-sized, and they're attractive fish to look at. They sometimes become a little bit aggressive with others of their kind if you have too many in too small an area, so something to keep in mind. The clown loach has a 'knife' on either side of its 'nose' that it can extend and use to cut the snails right out of their shells-- really cool if you ever get to see it.

Aughie -- that's a good diagram, really illustrates the cycle well. It also hits on something that I didn't think about, which is nitrogen gas emitted from nitrate in the soil. Anyone know how this works? My biochemistry knowledge only goes so far. (Read: not very far at all.)

I think we're hitting on something very important to a healthy pond, which is to look at the processes taking place in nature, and to either reproduce them or mimic them. It's a little tricky because a pond is a somewhat closed sysetm, and it's nature in miniature, but that's part of the challenge and the reward. It's also tricky because there is one factor, water clarity, which is not a symptom of a healthy natural pond; then again we're not trying to maintain the same biomass as a natural pond, so it should even out.

[Crushdepth]

If its still open - I'm not sure since they had a bit of trouble with the law last year - Safari World has a magnificent Koi pond with crystal clear water (if anyone knows how they keep the water clear I'd love to know).

[Ajarn]

Steve, in your description of a 'natural' filtering system using plants and other materials, I imagine it to be something like I just finished last month... Is this the kind of thing you're talking about?

(about 4 meters wide at the base, about 3 meters tall. Submersible pump (Japan, 1800 baht) behind rock wall. Fish include Koi, goldfish, and some big black ugly thing that cruises the bottom. Looks like it bites, too! )

As for the mango stuff, it's on another waterfall in a different area of the garden (Not even NEARLY as big as it sounds). it's a black sludge that's pretty hard.... I'll try to get a better photo this pm when swimming . I've worked two years on creating a perfect 'jungle' effect, particularly with the waterfall. The plants are too well established to remove without killing them, and the rocks are all set in cement. I want to minimize any adverse impact, obviously. My hope is that there is some magic stuff that will wipe all the bad shit away, and leave my little Garden of Eden intact, including all living things that don't bite me, or therwise annoy me. This is My World.

[chownah]

"I don't want to bicker, but plants definitely do not consume ammonia -- they can only take in nitrate. This is a well established scientific fact. ......."

I think you are mistaken here. If you are correct then the agriculture scientists at Mississippi State University, North Carolina State University, and the University of Edinburgh will be really interested in finding this out. Scientists at these universities have directly stated on the internet that plants can uptake ammonium (which is the ionized from of ammonia).

[Ajarn]

Okay, here's the waterfall, and a close-up of the gunk/mold..

Any thoughts on how to get rid of the stuff? We did a bit of scrubbing today, and cleaned the pond, so the condition has improved a bit from it's previous all-black look... Still a long ways to go, it seems.

[bkkmadness]

I think you are mistaken here.  If you are correct then the agriculture scientists at Mississippi State University, North Carolina State University, and the University of Edinburgh will be really interested in finding this out.  Scientists at these universities have directly stated on the internet that plants can uptake ammonium (which is the ionized from of ammonia).

How is Ammonium created? Is it a process which occurs in fish ponds?

It's different from Ammonia of course, which cannot be removed by plants.

If plants could remove Ammonia, then there would be no need for biological filteration in fish tanks and ponds.

Ajarn, I really think you do need to get in there and start scrubbing (or get the wife in there whilst you direct the operation with a beer on the sidelines! ). Without exactly knowing what the black gunk is it would be foolish trying to treat it with chemicals. Especially if the chemicals are strong enough to upset the natural balance in the pond. It's a hand on job as far as I am concerned which may be hard work this time, but let it be a lesson to you and make sure you prevent it from happening again.

My idea of natural filteration/vegetation filters tend to involve a lot more plants to rid the pond of nitrate but no doubt the plants in your waterfall will help to some degree. Looks great by the way!

Edited May 4, 2005 by bkkmadness

[Ajarn]

I think you are mistaken here.  If you are correct then the agriculture scientists at Mississippi State University, North Carolina State University, and the University of Edinburgh will be really interested in finding this out.  Scientists at these universities have directly stated on the internet that plants can uptake ammonium (which is the ionized from of ammonia).

How is Ammonium created? Is it a process which occurs in fish ponds?

It's different from Ammonia of course, which cannot be removed by plants.

If plants could remove Ammonia, then there would be no need for biological filteration in fish tanks and ponds.

Ajarn, I really think you do need to get in there and start scrubbing (or get the wife in there whilst you direct the operation with a beer on the sidelines! ). Without exactly knowing what the black gunk is it would be foolish trying to treat it with chemicals. Especially if the chemicals are strong enough to upset the natural balance in the pond. It's a hand on job as far as I am concerned which may be hard work this time, but let it be a lesson to you and make sure you prevent it from happening again.

My idea of natural filteration/vegetation filters tend to involve a lot more plants to rid the pond of nitrate but no doubt the plants in your waterfall will help to some degree. Looks great by the way!

<{POST_SNAPBACK}>

Thanks, BKK, it seems you're right. No magic happening on this front, it seems. Actually, there was never any question of me scrubbing anything . I just wanted to try to find an easier way for my workers, and minimize some of the damage that's sure to happen to the plants. It's not possible to keep it from happening again without cutting down 4 mango trees, and my landlady would kill me because she planted them herself, and she has this strong sentimentality that I can understand...

Normally, I never need to change the water for the fish (none have croaked in over a year, and that one happened cuz the cat got lucky) because the waterfall does a great job of cleaning- and bio-cleaning, it seems, too. but the first rains this year washed more gunk into the waterfall and pond than last year due to all the roof runoff now being channeled to the top of the waterfall... I'll make some changes there before this time next year.... Maybe. TiT

Thanks again for the suggestions

Edited May 4, 2005 by Ajarn

[aughie]

That may be your problem AJ. There is gunk/mold on the roof feeding on the tree residue and it gets washed down on the rocks every year. Maybe climb the roof have a look and get at the source? Clean the roof before it dumps on the waterfall.

BkkM,

There is no need for a filter in a marine aquarium if the ratio of fish to giant clams, corals and live rock is correct. Symbiotic algae in giant clams and corals feed on ammonium or ammonia (?). All that is needed is ocilating water jets to circulate the water and prevent sediment and freefloating algae from settling on the corals and blocking its light source.

Filters aren't needed in a freshwater tank either if the ratio of plant to fish is correct. Freshwater aquariums use a layer of iron rich clay mud under a layer of gravel for the plants to grow in. If I remember correctly this allows for anerobic bacteria to grow also. The water is moved very slowly thru the substrate by placing a heater underneath the aquarium. Dupla use to import the soil from Thailand. This method is at least ten years old I don't know what they are doing now.

http://dupla.com/

-a

Edited May 4, 2005 by aughie