Care to help me achieve best clearity ? Thanks


LifeTime Supporter
Apr 6, 2008
Hi All,

I just introduced myself a few hours ago in the Introduction section. Very friendly crowd here.

I want to say that this is a great forum. I would like to share and this case I surely will learn a lot.

I want to improve the clarity of my pool or better word would be maintain longer clarity of my pool , increased its hygiene level or health protection for the users. I am now obssesed with crystal clear water. It feel so good to be able to swim in a pool as clear as spring water. I think the effort is worth the result and achieving success in getting very comfortable water is like hard core audiophile being able to listen to high fidelity sound reproduction of musical instruments in their music room.

I like wearing diving mask and staring at my pool water.. underwater ...when its sparkling clear, it feels good for me.
I even try and can find hair on the bottom of the 13 feet depth section by looking for it from the surface, sort of a way
I measure its clarity without getting wet or using Secchi Disc.

I want to achieve water clarity like this pool :


I read that pure water technically has visibility of 74 to 80 meters.
Here is a test in Pupu spring, New Zealand.

I know many of you here are experts.
I have done much research and too much info over short period of time makes me "dizzy".

The more I know & learn, the more flaws I discovered on my pool.
This is why I said it is like an obsession to learn more and improve.

I will post some more later on what I been up to and learned. Hope you guys can assist me.

Many thanks in advance,



LifeTime Supporter
Apr 6, 2008
Hello All,

As I said in my introduction, I did really not get involved at all during the design of the pool because I never knew anything about pool.

All I did was :

1. Specify the depth and how big shallow end and deep end.

2. I do not want any drain that exist on the bottom of the pool where the pipes actually run into the pool bottom. So what builder did was to add drain pipe on one of the pool deeper end 90 degrees corner by hiding it inside an added thickness of the concrete. For some reason I am afraid of leak.

3. The designer spec out concrete thickness of 5.9 ". I don't know the rebar spacing, I guess its standard. However my home architect was worried due to the pool being so deep, he added the thickness to 10". I guess that should do. I don't understand anything about building.

4. I do not want any underwater lights. Being a drive training pool, I need good brightness even at night and underwater lights are expensive. I also worry of micro leaks on the holes made by the lights and problem of changing bulbs. So I stick to lights installed on the sunshade frame. This is also good because lights in pool is not good for dive training. Divers get blinded often and beam spread can never be good or 100% even, unless you put a lot of lights.

In the end the pool was built and completed in late 2006.


Now I a loosing water at a rate of about 100 gallons a day. I talked to the team and it seems they forgot to water proof part of the pool.... that is a big joke. It is the top of the pool about 10 inch or so width that leads to the overflow gutter.
They waterproof the gutter, but not that top part of the pool...crazy SOB.

I also regretted using a so called natural rock tiles ( I don't know the English word for it) for the pool surface perimeter floor. Those natural rock tiles absorb dirt and water too. My pool underwater is ceramic lined. This natural rock tile can only be cleaned using high pressure water, but the sand in them also got blown out of them. I hate it. However, they are not slippery at all...that is the good part.

I do not regret the sunshade and the water drainage on them. Without the sunshade, if there is big rain, all dirt from the building surrouding the pool will fall in to my pool from the walls. I do not have cloudy water even in the biggest rain, unlike some other pools I know. I just realized how important it is to protect an in-ground pool from rain water that travels from other floors surrounding the pool itself. Rain water itself from the sky, can't be bad, its is pure water produced by condensation, no amount of air based pollutant can make it any dirtier than a city air. It is the contamination they got from bulidings roof. wall and floors.

Since the pool area is small. All other floors ( even they have drainage ) the surround the pool perimeter get a washdown everyday. I have a staff that take care of the pool daily, so no problem.


When the pool was first built, it was only equipt with the sand filter. So when doing a vacuum, the valves must be selected to WASTE or else the fine particles will come back to the pool if set to FILTER mode. This is expensive and not eco friendly. City water here is US$1.1 per 1,000 liter ( 264 gl ) . Initial pool filled was using what supplier called, natural spring water
( but a bit green at the deeper end of the pool...ha ha ha ) and expensive, need to be send out in trucks at US$40 per 8,000 liters ( 2,116 Gl ). I need at least 16 trucks. That is already US$640. The city water flow is slow flow, unlike in 1st world countries. I will need 1 to 2 weeks to fill up my pool if I use city water and my building will not get its share of water.
I can't wait this long. My area has lots of ground water ( brackih though ), digging the pool itself, the ground produces water already. If I wait too long keeping the pool empty meaning it will be light, it may float up due to hydraulic pressure from ground water. This happens already a few times in area close to the sea. Lucky for me, I actually have a diver friend who is in pool supply business. HHmmmm, I should have known earlier and contracted the job to him.

So when the Feb 2007 flood came, I started personal involvement. A good friend gave me a present, that is an Aquamatic MK 5 ( Aussie brand ) Silver & Copper ionizer. I bought an extra Hayward cartridge filter downstream of the sand.

Why I bough the cartridge filter is because, I learned that sand filter is only up to 40 micron filtration at best. Some say its 100 micron ???? Thus this is the reason I am getting back fine particles when I vacuum and filter set to FILTER setting.
I think the Hayward cartridge is 20 micron or so. I don't want the DE because I don't want extra burden having to put DE powder but I love the DE spec of 3-5 micron. After the installation of the cartriged filter, I see a remarkable difference.
My pool is deep at 13 feet for the deeper end. If water is not clear, it becomes so obvious. I can't see fallen hairs on the deeper end. Unless water is clear and algae free, the deeper 13 feet section will give me the greenish color, I hate it.

Because of my pool is in a big city and Jakarta is dirty and polluted. Vacuuming is done every two days or everyday after divers used the pool. I don't use a robot, I use a human...ha ha ha. Bear in mind, a diver uses full wetsuit, tanks and BCD and all sort of contamination carrier. It is so easy to tell the fine particles the divers brought ( even though equipment are rinsed before use ), I get to see the cartridge filter pressure rise up about 2 psi per 4 divers using the pool for 3-4 hours.
On average, the cartridge filter get cleaned about once a week or after 3 days dive training session. Even without divers, no such thing as more than 2 weeks without cleaning the cartrigde filter. This shows how dusty and polluted Jakarta city is.

Well, I never actually got to sending my water to a lab. However, chlorine use does get reduced. I can't say accurately by how much because diver's load is never the same each month and I do not have the expertise like Chem Geek plotting chlorine use with such incredible knowledge. I did have initial problem with my ionizer. My TDS is so low, I am not getting enough conductivity in the water to push the unit to work at maximum output of 240 milli amps. So I added calcium chloride as instructed and I do it so very slow, it took me like 2-3 weeks.

Hell yes !!!! My pool is one of the rare one in the country that uses Zelbrite to replace the sand filter. No one stocks them in the country because they are too expensive. So I have to ask my pool supplier friend import from Australia. So after tax and special dedicated shipping, I paid like US$ 500 or so to fill my Hayward, I forgot exactly how muh. It was money well spent. Water clearity improved in a way I can call it sparkling. With Zelbrite, chlorine use is lessen further.

However, there was some sort of conflict between Ionizer and Zelbrite. Zelbrite trap ions produced by the ionizer, since Zelbrite works based on ion ecxhange.

Aquamatics told me this :

"Avoid the use of Zelbrite or any zeolite filter media. It may filter finer and absorb ammonia from the water but it also adsorbs copper ions so it rather defeats the purpose of having an ionic system. There is a new glass filter media available from Poolrite Qld, called ‘Diamond Kleen’, which may be worth investigating (part of their Magna Pool system"

So I wrote to Zelbrite to see what they will say and they reply as follows :

" Yes it is true that Zelbrite will pull out copper and silver but it being held in the media it will still work --- the only thing is that you will not get any reading of copper in the water as it is all being held in the filter. Once the media has pulled out as much copper as it can hold
you will then start to get a copper reading in the water.
Zelbrite has been on the market for 8 years any many pools around Aust have been using
your system with our media with great success."

I also asked Zelbrite how long does it need for a Zelbrite to get saturated with the copper and silver ions untill a surplus ions are finally released to my pool water ? They answer as follows :

"The sanitizing will be done in the filter as the water passes through --- the saturration will take 3 to 4 months --- if you wanted to speed this up you could always add a copper based algecide. The copper and silver will not harm the Zelbrite nor will if have any effect on the ion exchange."

Being wanting to know more, I ask again to Aquamatics, to know how much ions I am getting from my ionizer and how long do they last. They reply to me :

The first two postulates of Faraday’s Laws, below indicate that the mass (weight) of copper/silver ions released is directly
proportional to the quantity of electricity used (see attachment).

First Law
The quantity of a substance produced by electrolysis is proportional to the quantity of electricity used.

Second Law
For a given quantity of electricity the quantity of substance produced is proportional to its weight.
The quantity (number of electrons) is expressed in amperes per unit time (seconds). One ampere flowing for one second is called one coulomb.

One gram equivalent (equivalent weight (molecular weight/valency) in grams) of any substance is equal to 96,500 coulombs.

The equivalent weight of copper is 63.5/2 = 31.8 (approx)

The equivalent weight of silver is 107.9/1 = 107.9 (approx)

The electrodes consist of 95% copper and 5% silver by weight so the ratio of the weights of ions produced are proportional to the atomic weights, 31.8 x 0.95 = 30.2 (for copper) and 107.9 x 0.05 = 5.4 (for silver) so the ratio of copper ions to silver ions is 5.6:1. That is 5.6 copper ions for every silver ion.

Calculation of Rate of Production of Ions

We know that 96,500 amp seconds will produce 31.8 grams of copper by electrolysis.

So 1 ampere flowing for 96,500 seconds (26.8 hrs) will make 31.8 grams of copper ions.

So 0.25 ampere flowing for 26.8 hrs will make 31.8/4 = 7.95 grams of copper ions or 7.95/26.8 = 0.3 grams per hour.

1 mA of current flowing for 1hour = (0.30/0.25) = 1.2 mg copper ions and (1.2/5.6) = 0.21 mg silver ions.

As a rule of thumb, the copper ions need to be replaced in a pool approximately every 20 days so for a 50,000 litre outdoor pool

with a 6 hour filter cycle it would need to produce 50,000 x 0.6 mg in 120 hours. As you can see from the data above, it has the capacity for this volume of water. The usable weight of a pair of electrodes is approx. 700 grams and the usage is 1.5 grams per day so the expected life of a pair of electrodes is about 1.3 years in a 50,000 litre pool.

I read a few warnings on the Aquamatic Inonizer unit, so I emailed to them again :

No copper based-algecide ( Ionic stater is copper sulphate pentahydrate )
No Bromine compounds
No aluminum clarifiers
No chlorine stabilizer ( eventually high level Cynuric acid problem, with low PPM chlorine or CYA detrimental to Aquabrite ? )

Aquamatics reply :

" The reason we say don’t use copper-based algaecides is that they do not contain silver, whereas our ‘starter kit’ does.

Bromine compounds release bromide ions which react with silver ions to form insoluble silver bromide, the coating on photographic film. When the sun comes up the pool interior surfaces turn black. At night it fades and repeats the next day etc.

Aluminium clarifiers adsorb both copper and silver from the water, leaving the pool without sanitiser.

Low levels (30ppm) of stabiliser are usually O.K. unless the water is very high in calcium ions, when an insoluble double salt of copper can be formed…like pale blue talcum powder. Iso-cyanurates are not usually required in an ionised pool. If chlorine is required it’s best to add it in the evening to obtain the maximum effect."

So, being stubborn and willing to experiment, I go ahead and bought the Zelbrite. My logic is like this.
I run my at least pump 12 hours a day. If those copper and silver ions are parking themselves in the Zelbrite, it doesn't really matter because I am supposedly supplied with a 8 hr 1 turover pump. So I am getting 1.5 turover everyday and I hope all those nasty bacteria get more beaten up by the masive ions parking in the zelbrite...ha ha ha.

So how long did my inonizer rods last ? About 8 months, and I set at 180 miili amps and run the pump on average 16-18 hours a day.

WILL CONTINUE......................


LifeTime Supporter
Apr 6, 2008
The thing I hate about Indonesia is that, there is no regulatory body when it come to pool professional or pool supply stores.
I mean to say is that, I have not yet find a pool profesional ( maybe I did not try hard enough I guess ) that can understand pool chemistry the way I expect them to understand to at least a minimum level. I can't speak to any technical sales that can answer me like how a good computer sales tech can reply questions.

I guess pool supply is a small business in the country, so the mentality is pure business.

I like asking critical dan difficult questions. As a retired dive instructor, I used get hammered lots of dive science questions from students and many fall outside the real diving itself but strongly related to marine bilogy or divers physiology and so on. Its something I hate to keep up but must do. I expect pool professional to be a "real" pool professional, like many in this forum.

This is why I said, the more I learn, the more flaws I discovered with my pool.

My main trade is selling yachts. As part of the job, I also do troubleshooting both electrical and mechanical ones if not a a very dificult cases. I focus my attention on fuel filter, I mean the more in depth study of it.

SECOND PUMP & FILTER- Mobile Unit on Trolley

The reason I bought these are simply because by design, I felt that my pool water circulation is not that good.
One day I decided to clean my pool and use a scuba tank, because I wanted to scrub each and every tile flooring grout on the 13 feet deep section. It took me like 3 hours, because I was using a toothbrush and holding a vacuum hose. I always thought that the black color on some part of the grout was black algae, but it wasn't. It was raw cement, where the white grout putty has came off. However, on the corner where the shallow pool section meet the deep one, the drop off I call it...I spotted 2 areas of at least 2" long, it has green algae.

My pool has a total of 8 inlet nozzles. 3 x 2 on length and 1 x 2 on the width of the pool. It is located about 10 inch below water line. Even though the usual setting of the valves are : DRAIN and BALANCING ( SURGE ) TANK being opened, I still think that the deeper 10 feet part of the 13 feet deeper section, does not get good enough water circulation...hence the green algae on the two spot I mentioned. It makes no sense that my pool water is clear and yet I have 2 small area with algae growth on the grout. I am having a dead zone in the pool.

So I told my staff. Everyday for at least 4 hours, closed the balancing tank valve so that the drain at the deepest end of the pool will be the only one sucking water. I am hoping that at least the satitizer circulation will be improved. I also set all nozzles towards the pool bottom.

I got the back up pump and filter on trolley, is to make sure I am getting better circulation. I estimated 4 hours per turn over if back up and primary pump run together and if I run them for 24 hours, I can get much better circulation when needed in shorter period. In fact this really helps. In busy days, I can maintain clearity easier and faster recovery.

No matter who say what, achieving a complete filtration of every drop of my water in my pool using the general rule of thumb of pump size/flow against total volume of far from accurate, more so with my pool having an odd design.
Unless I have two pools with same water volume and transfer from one filled one to the other empty one, there is no way
to guarantee a 100% filtered water. A 100% turnover by volume ...YES. If for evey liter of water in my 135K liter pool has a name, I bet at least more than ten thousand names do not get the chance to reach the filter, if based on traditional 8 hours cycle. I regretted I do not know anything of pool science when my pool was built. If I were to make a new pool, I will make sure I have these :

01. DRAIN holes, make 4 on pool deeper parts, located at all corner. Now I only have 1.

02. No more than 4 inlet nozzles per 1 pipe servicing them with valves to isolate each pipe. I want less resitance and better control of water flow.

03. 50% more inlet nozzles than what I have now.

03. A lot more inlet nozzles on shallow pool end. This way I am assuming I can create water movement, and thus better distribution. If I shut off some nozzles around deeper end only, open the shallow ends ones, close suction in balancing/surge tank and open all 4 drains in deeper part of the pool...I think I can create better water mixing and I get more evenly spread sanitizing. Would need expert here to help me out, if my assumption make sense or not ?

Find attached the back up pump and filter on trolley photo.