When Is Water Not "Saveable"

[rick99]

Hi....me again,

So I bought the best water available for my pool start up; and it was beautiful.......clear and perfect. But then no one showed up to start the pool. I had no chemicals and no test kit. I watched the water turn green and then cloudy. After two days they finally started working on the ph and now have added algicide and a ton of trichlor. It still looks and smells terrible.....like a chemical bath (very cloudy and green). The first test (after the two days of sitting in the hot sun) showed some weird colour of PH.....not even on the test kit......and no chlorine.

The builder and his water expert tell me that this is standard start up. I am not happy because the water was perfect.....now has gone bad....and they are trying to recover it. So........at what point is water bad.....and cannot and should not be saved???

Hmmmmm any thoughts????

[PoolDoctor]

Sounds like you have a great relationship with your pool company. All water is saveable, chlorine kills the algae, which is then vacuumed up and filtered. We have recovered pools after several years of neglect. The only time we drain is when there is "sludge" in the pool and a danger of clogging the filter. That being said, there is no excuse for your company to let the water get that bad (they can start the system with 1" in the pool - circulate via the main drain). pH is only moderately related to green water, the key is to have enough free chlorine in the water to keep it clean and clear. Why is the pool not on a salt chlorinator system?

A couple of points - algaecide is nasty stuff (turns blonde hair green) and uses heavy metals like silver to kill algae. Those metals do not evaporate. I would not let my own kids swim in algeacide treated water. Also, triclor has a pH of about 3.3, meaning heavy doses of it will turn the water very acidic very quickly. This is not great for the pool grout, which will disolve in about 2 months if you do not correct the pH upwards.

There is nothing standard about this startup, especially with clear water to start with.

[Chaichara]

If they are charging you for the chemicals the reason is clear why they made you wait until the water went green. Like all pool supplies, the price of chemicals also varies widely; For a 3.78 litre bottle of concentrated algaecide or clarifier, you could be paying as much as baht 1,850 from a pool shop. They are buying it from the wholesaler from 600 or so. Go figure.

[WarpSpeed]

Most of what both BM's said above is true and algaecide is a waste of money and sales tool as the CL2 should do much of the work without it in combination with the filters/filter unless you have sand filters which are pretty useless where clearing pools are concerned.

If you do have sand filters the algae can also live in them if not treated separately after all it is sand and algae is plant life so not treating the filter could result in a second or continued contamination of your pool..

As for algaecide turning blonde hair green that's not true at all it is the combination of high cl2 in conjunction with a low PH that does that and it causes a bleaching reaction, though trichlor does drop the PH considerably especially if your total alkalinity is already low as well. These need to be brought back into balance once the pool is no longer green and the PH in tandem with the T/A needs to be brought up to coagulate the suspended algae so it settles to the bottom for removal but they should be using liquid Cl2 instead as trichlor and all powdered chlorine products such as tablets raise your total dissolved solids which is what algae eventually feeds off of kind of perpetuating the circle..

But if done properly your water is fully recoverable it's always just a matter of finances when a decision to change water is to be made, bottom line will it cost you more in chems to recover it or to refill it?? Which will also require a chem balancing..

Edited July 14, 2010 by WarpSpeed

[BB1950]

I've never had to discard water, even when the pump was out for a rebuild (several months) and the pool turned really yucky. It's always savable. For some reason the Thais think you have to replace the water, you don't. You need to run the pump longer, vacuum and brush the pool (don't forget to brush the walls the brushing breaks down the algae, so the chlorine can kill it easier), backwash the filter or wash the sand (depending on condition), and check the chlorine daily. The water looks and smells great in less than a week.

I've quit using an algaecide or water clarifier years ago. I found it was expensive and not very effective. Plus I don't know what's in it. The manufacturers seem to want to keep it a secret which bothers me. Instead, I've found that if I use a very small amount of copper sulfide the algae dies rapidly and the water is crystal clear the next day. Be very careful, too much can turn everything blue. Use it sparingly and only when necessary.

I would keep the water slightly high on the chlorine side for a while, as most likely the water you bought didn't have any chlorine at all (most likely from an underground well), which is likely why it turned green so quickly. If you have a lot of algae, you may need to super-chlorinate the water. The Thais like to use very little chlorine as they feel its too expensive. In the past, I've always had problems with them not using enough. Remember direct sun breaks the chlorine down very quickly, so you need to check it frequently. Powdered chlorine dissolves in the water much more quicker than granulated. I would only use granulated chlorine to maintain the chlorine levels are established.

I've been told that with using salt water, you don't need to use as much chlorine. I'm no expert on salt water usage, but it does sound healthier to me. In the past, salt was very hard on pool equipment, but nowadays almost everything is made plastic or rubber. Unfortunately, I don't know anyone who's an expert, nor have I seen much information on-line.

Get the chlorine level correct first. When you get rid of the algae, you can gradually reduce the chlorine. Way too much chlorine can give a false reading for the pH test. So don't worry about pH level too much at the start. The only thing is you don't want it acidic. After the pool is set up, in order for the chlorine to efficiently kill the algae once the pool is setup, the chlorine and pH levels should be balanced. Also when you use the pool, if the pH is incorrect, your eyes will be irritated. I've also notice that Thais tend to keep the water rather acidic and don't use soda ash to raise the pH. They're always wanting to add acid instead. Many don't even know what soda ash is.

Acidic water is very hard on the grout! Once the grout disappears you may have a leaking pool. Also not enough chlorine and lack of brushing will cause the grout to turn black from fungus. At some point you might notice a rusty looking yellowish color developing the pool fittings and grout. That's mustard fungus! It's very easy to get and very hard to get under control. You have to super-chlorinate the water often, brush daily, and use copper sulfate to help get it under control. You will never ever get rid of it, because it's inside the pipes and equipment. Replacing the water won't help. Once you get it, you always have to maintain a higher than normal chlorine level, brush, and backwash often. I've been told that it gets started by someone entering the pool with contaminated swim clothing.

Also, it's possible that even though you bought good clean water, they probably didn't wash the sand in the filter, which would make the pool cloudy very quickly!

I've never had to use triclor and never will! It definitely will turn your hair a greenish tint.

[PoolDoctor]

Hi, just wanted to correct a couple of points above:

1. Algae cannot "live" in a sand filter that is being maintained and flushed properly; lack of sunlight and high flow rates confirm this. Algae requires sunlight.

2. High chlorine does not turn hair green (but it might bleach it); it is the copper in the algaecide that turns hair green; much like an oxidizing copper penny

3. Salt systems generate their own chlorine (from the salt - sodium chloride) so no external chlorine is required

4. Trichlor (this is a nickname for Trichloroisocyanuric acid (C₃Cl₃N₃O₃) is the granular form of chlorine widely available and used in pools in Thailand. 90% strength, but very low pH. It will dissolve grout faster than a red shirt mob burning buildings. Does not turn hair green. Only a copper-based algaecide will do this.

5. pH also should be checked and adjusted if on the high side (somebody mentioned only when on the low side [acidic] is it dangerous); reason being, at high pH (base) the "killing power" of chlorine diminishes greatly to less than 20% efficiency. This graph is wide known. http://www.hannainst.co.uk/page/Chlorine-Explained/

6. Adding tri-chlor to a pool continuously over years does raise TDS (total dissolved solids) due to the cyuranic acid levels build up. TDS is everything in the pool that is NOT water. Algae can not feed on inorganic TDS (metals, chlorine, CYA, etc); however, it is thought that high TDS encourages algae becuase high TDS levels MAY inhibit chlorine oxidation. TDS is very widely misunderstood the world over, even more in Thailand. This topic is currently being researched.

[craigt3365]

That comment about Trichlor dissolving grout kinda scares me. Our pool comes 2 times a week and uses granular chlorine. He throws it in and lets it sit. I guess that is not good?

What can I recommend he use instead? Liquid chlorine? Maybe I will have to buy it for him and then he will use it? I notice you have an office here in Pattaya. I might stop by...

[buckhumyai]

A couple of points - algaecide is nasty stuff (turns blonde hair green) and uses heavy metals like silver to kill algae. Those metals do not evaporate. I would not let my own kids swim in algeacide treated water. Also, triclor has a pH of about 3.3, meaning heavy doses of it will turn the water very acidic very quickly. This is not great for the pool grout, which will disolve in about 2 months if you do not correct the pH upwards.

There is nothing standard about this startup, especially with clear water to start with.

I have a swimming pool company in Australia, and would like to add my 2c.

Whilst the pooldoctor is very knowledgable I must disagree with one statement that algaecide is nasty stuff. Trichlor and Hydrochloric acid, now thats nasty stuff, however when stored and used in the proper manner is usually quite safe. However don't mix the two or you will make mustard gas and can kill or seriously injure yourself quite easily. I know of two pool service technicians who have been hospitalised by accidentally refilling sodium hypochlorite (liquid chlorine) into the wrong container, which was filled with hydrochloric acid.

The majority of algaecides on the market are copper based algaecides. The World Health Organisation have set the safe level of copper in drinking and swimming water at 1ppm. Most algaecides work effectively with a dosage of about 0.3ppm copper. Several kinds of algae have shown to be very chlorine resistant especially blackspot algae and mustard algae and can consume massive amounts of chlorine to eradicate them, or an algaecide with normal levels of chlorine. I have seen cases where people have saved quite a bit of money by using an algaecide especially in Commercial pools where the chlorine demand can be very high. I would guess I have sold 10000 bottles of algaecide over the years and never seen any problems.You must use a quality algaecide where the copper is present as a complex ion and it can not plate out and cause staining. Unfortunately there are several cheap chinese made products that could potentially cause the problems pooldoctor is talking about, however only if it is overdosed and the water balance is not correct to begin with.

I use a Palintest photometer hooked to a laptop to check water and often do copper tests for commercial pools. to determine if the addition of more algaecide is required. I can assure you that the copper is consumed in the reaction and is eventually filtered from the water and does not build up with time as the pooldoctor suggested. If you are concerned about adding copper to your water, there are also several non metal based algaecides which are also very effective with standard green algae. Benzalkonium Chloride for example is the same stuff used in eye drops to stop algae forming. How dangerous can that be?

When using salt water you must superchlorinate regularly during the swimming season ( This will be in every instruction manual for every chlorinator ever made.) How else can you destroy Chloramines?

Finally using trichlor is no problem at all in tiled pools provided the water is balanced. It is not the trichlor that dissolves your grout, it is the effect the trichlor has on the water over time, of lowering your pH and alkalinity and making the water very acidic which causes the problems with your grout.. In theory all tiled pools should be balanced according to the Langelier saturation index between 0.2 - 0.5 which means the water is slightly scale forming and will not corrode the grout. To do this you need to know the pH, Alkalinity, Calcium Hardness, the temperature of the water and how they relate to each other.This is probably unlikely to happen in Thailand so I would suggest telling your pool guy to maintain an alkalinity of 150ppm as this will buffer your water and make it more resistant to sudden and dramatic pH change, thus protecting the grout in the pool. Also make sure your Cyanuric Acid or stabiliser level is not more than 100ppm as this could potentially, although very rarely, cause problems. The pH and Alkalinity will be gradually lowered by the regular addition of trichlor, so you need to ensure you maintain the alkalinity at 150ppm.

If your pool guy cant tell you what these levels are and just gives you one of those Thai blank looks,then find a new pool guy.