Need Advice On A Huge Chlorinated Pond

[tkalla2000]

Hello, I have a pool service in south Texas. I have taken care of hundreds of pools but this I have never seen before. I have taken on a job at a mulit-million dollar HOA to take care of their center piece pond. I have never seen anything like this before, but apparently neither has any of the other service companies in this area because they have failed to maintain this pond. Just guessing I would say it is about 200' long by 150' Wide and about 2'-3' Deep. I would say probably 100,000+ gallons. I think the equipment is right and big enough to handle this much water, but my fear is keeping chlorine in the water seeing that it is so shallow and the temp get pretty high down here in the summer. The equipment that the builder put on it is as follows;

3 Triton II TR140's (925lb's a piece) Sand filters

These are powered by 3 Jandy Stealth 3hp pumps. 2 for the waterfalls 1 for the infloor cleanersystem

1 Commercial Rainbow chlorinator (holds about 50 3" tabs) plumbed with 1" PVC

A Jandy aqualink RS8 controls all this

There are 6 skimmers 12 main drains and 4 leaf trappers

There are about 150 popup heads controlled by 4 Polaris ultra-flex 2 controllers and caretaker heads

The first obstacle I have is how to vacuum the bottom. The pond floor is made of stones and I have tried a few conventional vacuum heads and have not had much luck, the stone are to big. I am getting a portable vac system but I still have to come up with something for a vac head. The skimmers all work but this is a gulf side property and they did not consider wind direction when they put the skimmers is so most of the leaves blow to the end of the pond where there is no skimmer. By the way this entire pond is surrounded by live oaks. The leaf trapper system seems to have good flow to it but does not pick up many leaves. I've been having trouble keeping chlorine in the water. It's been using about 50lbs. of chlorine per week and the chlorine level will come up to about 4ppm then down to 0ppm

the next day. The water stays clear but the bottom of the pond is starting to grow green algae. I fear this is because the shallow water allows the sun lite to penetrate all the way to the bottom but I am not sure of this. Right now it is filled with well water. I would never use well water for a pool but the HOA insisted that I try it. We are only about 7 feet above sea level here and the well water is terrible. An expert tested the well water at the tap and said the TDS was 3100 and 2800 of that was salt from the nearby sea water. When I herd that I told the people in charge that it would never work with that water. They are now in the process of piping city water to the pond. I would like to know if anyone has delt with something like this before or does anyone think this will work once the city water is piped in?

By the way the chlorinator is plumbed into the infloor system so it gets distributed across the pond pretty good. It might need another chlorinator, I don't know. The original setup had 2 SWG's instead of a chlorinator. I shut them down because the well water ruined the cells and I don't think chlorine generators would work on this application (not enough chlorine and way way to hot down here).

If there is anyone out there that has any experience or any ideas for this monster of a job I would appreciate any help I could get.

[Strannik]

I'd say if you already have salt in your water, your best option would be to use SWG.

How exactly did the cells get ruined?

We have supplied commercial SWG's for the shallow pools with big surface area in tropical countries and they all work fine, provided that the sizing is done correctly.

As far as we are concerned you can even just use pure sea water, provided you filter the debris out before it gets into the pool.

Can you post your full water test results?

With regards to vacuuming, you might need to make a custom vacuum head. The idea that i have in my mind, is something like the stuff you use for vacuuming fish tank. If you make it out of soft resin it should work fine, for small to medium size stones.

Can you post some photos of the pool?

[tkalla2000]

For the price it would cost for a commercial would be to high. I am the third pool company to take on this job. The last 2 came at them with $20,000 bids and scared them off. I would like to use chlorine tabs, at least at first because I know if I put enough chlorine into the water, It will keep up. I have never seen any of the high dollar SWG in action before and I would not be comfortable selling something that expensive unless I know it will work. I will post a copy of the water readings when I go out there on Tuesday. I have a couple of photos I can post but I don't know how to post them on here. If you could let me know how to post photos, I will be glad to put a couple up. I really would consider SWG but there is about $350,000 invested in this pond and they are still not happy with the results.

[tkalla2000]

Here is a link to one photo http://www.flickr.com/photos/28177673@N04/2629160678/

[Strannik]

Lets wait for the test results, but first thing you need to do, in my opinion, is get that algae under control by shocking the pool with liquid chlorine.

Once you know your CYA level (if any) you will know how much bleach you need.

With regards to vacuuming, it looks as so the stones are not that big, so if you make/get something like fish tank syphon, but bigger, you will be able to vacuum it successfully.

If you were to go with an SWG, you would need something like our SRC-400 to do the job. It retails for somewhere around 15-25k (i don't remember the pricelist from the top of my head), so yeah, it would be out of your budget.

But i would suggest to get the water chemistry under control first before investing in any equipment .

Also, do you get ducks, or other birds in that pond? I would also stop using chlorine tabs, since they have CYA in them, and considering the amount you use, your CYA level will climb up very quickly, blocking chlorine from doing it's job.

[tkalla2000]

Well I would shock the pond, but they are in the process of piping in the city water so I think I'm going to drain it and pressure wash it and then fill it up with clean city water. I don't think there is any other way to chlorinate it without the use of tri chlor tabs. Mabey there is a way that I don't know about, but down here the UV rating is always high and the temp is 90 too 100 most of the summer and tri chlor seems to be the only thing that keeps up.

[Strannik]

Is partially draining and refilling it every now and then to decrease CYA an option?

[Pathfinder]

You may want to check out ECOsmarte I know we all have different opinions on Ions but I have seen a couple projects they have done in the Min. area & the water features looked great. I wouldnt use the system for a pool but ponds and water feature id consider http://www.ecosmarte.com/fallingwater.htm

[tkalla2000]

Yes, I could drain about one third of the water every few months if I have to. It also take quite a bit of water to backwash the 3 big filters.

[tkalla2000]

Thanks for the link pathfinder. I checked out the video and it does look interesting. I wonder how well it would work in the intense heat of August and September down here. The only worry I have about putting all my faith into a gadget is that if it does not work, how do I explain a $9000 bill.

[ps558]

Thanks for the link pathfinder. I checked out the video and it does look interesting. I wonder how well it would work in the intense heat of August and September down here. The only worry I have about putting all my faith into a gadget is that if it does not work, how do I explain a $9000 bill.

I am not sure if this will work on your job, but I am using a aqua-trol system on a pool and it works pretty good and this pool get abused. The system uses sensors the regulate the PH and calculate CL and then pump the required amount of liquid chl in the pool. here is a link

http://www.acu-trol.com/pro-ak110.htm it is not a Goldline SWG. As for regulating ph mine only can lower PH, but I am sure it can do both.

It works good because if the water change the computer can react right away. Just a thought

[tkalla2000]

Here are the results from the water test.

CYA = 85

TA = 120

CH = 360

PH= 8.0

CL = 4.0

Water is clear but bottom is covered in green algae. This is with the well water @ 3200 TDS. I think I'm going to drain it in the next couple of days and fill it with city water. The water seems to stay clear in the pond but when put into a glass it looks brown. Also when I backwash the filters the water is very brown in the sight glass.

[Strannik]

Don't worry about TDS, it doesn't affect the algae growth.

With regards to CYA - you are already over the top so you shouldn't use Di- or Trichlor anymore.

With that level of CYA you'd need to keep at least 8.5ppm FC, and since you have algae i would shock it to 30ppm FC for couple of days.

Is anyone actually swimming in this, or is just a piece of landscaping?

[tkalla2000]

Nobody will be swimming in this pond. It is just a center piece to their landscape. What would I need to set it up for liquid bleach and are there any disadvantages to using bleach?

[Strannik]

with liquid bleach you have 3 options

Option 1 - do it manually.

Option 2 - Use Liquidator. It's sort of a bleach dispenser. I haven't had any experience with those, and i don't know if they have a model which will hold enough bleach for your pool so you don't have to refill every day. God think about it is that it's cheap.

Option 3 - use a proper liquid chlorine dispenser like Chemigem.

The only disadvantage of liquid bleach is that you have to cart it, store it and handle it. Other than that it's virtually perfect.

[tkalla2000]

Thanks, I think this could be an option. I could probably have them install a tank and dispensing system. I was doing the math yesterday and the bill for the amount of trichlor they use in a year was around $10,000. This is a HOA so I don't think they will want to spend $30,000 to $40,000 per year to run this thing. I think the electricity, water, and maintenance charge are going to be pretty expensive, so if I could cut down the chemical cost it would really help.

[Strannik]

SWG would probably even more cost effective, since you don't have to spend money on liquid chlorine. Initial investment would be higher but then it would catch up in couple of years.

[Safrole Jay]

You really need to send me those ruined cells from the old SWG system! See my other thread; I've always got a project cooking. Email me at jay@3rdgendecals.com.

I think you can trust the SWG people to deliver for you even at this scale. I first saw this process in action at my sister's enormous "neighborhood" pool in Canton Georgia. Not quite as hot there as you perhaps, but still shallow and huge.

Here it is.

Google Satellite

[Strannik]

I'd be interested to see the pictures of those cells, and to hear more about how they got ruined, because to ruin a good cell you need to do some unusual stuff.

[tkalla2000]

Sorry for the slow response. I will try to get some pics of the cells. I think they are ruined because I tried to clean them 3 times in a acid/water solution and they still look bad and won't work. I'm not sure what all was in that well water but the inside of the PVC lines is stained black and all the pump baskets are stained dark brown. I know that the company that was taking care of this pond before me had shut all the pumps down for an extended period of time, (I don't know how long) because the water in the pond was black and there was ton's on algae in all the lines and filters. They're reason for the pond turning black was that all the equipment was bad because it's Jandy pumps and Pentair filters, and they said it needed Hayward equipment.

[Strannik]

They're reason for the pond turning black was that all the equipment was bad because it's Jandy pumps and Pentair filters, and they said it needed Hayward equipment.

Hmm that must be why.... I hope you've changed all equipment to Hayward as soon as you got the pool?

With regards to the cells - repeated cleaning will not damage them (unless you cleaned them with the steel wire brush, or screwdriver). Post some photos, we might be able to give you some hints.