Swimming pool prob?: Off-topic discussion forum: Grassroots Motorsports Magazine

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Aug. 4, 2008 10:03 p.m. petegossett Dork

First of all, I don't swim, I sink like a stone...but the kids love swimming & I have a friend/neighbor w/a pool. He's been letting the kids swim all summer & I keep asking what I can do to help, well aparently now it's time!

He inherrited the pool(and the house where it resides)when his father passed away about 4-years ago. The pool sat unused & untouched until this summer. Don put alot of work & money into getting the pool ready this year, and everything has been fine until this week. He apparently has an algae problem, as the water is green. Yet, regardless of what/how many chemicals he puts in to the pool, the water never clears up. He mentioned something about using 4x the prescribed amount of de-algae-ifier-stuff(whatever it's called. lol), 2x the normal shock treatment, all on top of the chlorine tablets, plus backflushing the filter several times per day - all with no positive results. He was curious about the filter, but everyone he's asked states they never go bad. I'm wondering if that's still true even if the pool was untouched for several years.

I know nothing about pools, other than(like boats)they're something I refuse to ever own. But as a return favor to Don, I'd like to help him out as much as I can. Any suggestions?
Aug. 4, 2008 10:18 p.m. wlkelley3 Reader

I had an issue like that with my pool when it wasn't used one summer. I scrubbed the sides and bottom to loosen the algae and took a water sample to the local pool supply store and added the chemicals they said to add based on the sample results. Problem solved. Kind of sounds like it could be a PH balance issue as that was what my problem was. Too low, raised it and no more algae. The test is free, they get their money selling the chemicals to you.

I've heard that converting to salt water also prevents that problem and is easier to maintain, although expensive to convert. Think salt filter like water softner.
Aug. 4, 2008 10:40 p.m. MrJoshua Dork

Shock the living bejebus out of it. High regular levels of Cl- (around 5ppm) kill algae leaving dead algae carcases to feed the next generation of algae. You need greater than 30ppm which will actually completely destroy the algae leaving nothing to feed the next generation. You also need to get the pH right. Using liquid Cl- you get from the pool store. Muriatic acid you can get from the pool store or hardware store. And adding Cyanuric acid a few times of year you can run a pool with minimal work.

Looking through my old bookmarks from when I ran a 180,000 gallon pool for a few years, I think these are the good ones:
http://www.poolforum.com/pf2/index.php

Heres a good calculator:
http://www.csgnetwork.com/poolchemcalc.html

What kind of filter does he have?
Aug. 5, 2008 7:00 a.m. grtechguy SuperDork

get "Spot-Kill" then scrub the crap out of it.

1/2 bottle of water clarifier

resume normal shock.

this spring was a killer on our pool
Aug. 5, 2008 7:00 a.m. petegossett Dork

Thanks for the ideas & suggestions.

I believe he said it's a sand filter.
Aug. 5, 2008 7:28 a.m. MrJoshua Dork

Most of the fancy named stuff for pools is really basic chemicals in special labeled bottles. What this usually means is you end up spending more for the same stuff you can buy without pool specific names. Its all for sale at pool places.

The pool I ran for several years has run for at least the last 20years and probably the last 50years with a sand filter and a few basic chemicals.

Liquid chlorine (sodium hypochlorite)-for regular sterilization and occasional shocking

Muriatic acid or Hydrochloric acid-for pH and alkalinity control. (Chlorine drives the pH up and muriatic drives it back down)

Cyanuric Acid-Stabilizes the Chlorine. Chlorine is destroyed by sunshine. It has a half life of something like 20 minutes in direct sunlight. Cyanuric helps slow this process. Too much though and your Chlorine just sits there happily bonded with the Cyanuric and doesnt help your pool. Thats often the problem with stabilized Chlorine tablets. They usually contain enough stabilizer that you can lock up all your chlorine.

For his pool I would add enough muriatic to get the pH down between 7.0-7.3. I would then add enough liquid Cl- to raise the concentration to over 30ppm. Scrub, run the pool cleaner if you have one. Sit back and wait. At that point backwash the filter. At that point you should have a clean pool. Adjust the pH to the 7.4-7.5 range with muriatic. Then start using stabilized Chlorine tablets to maintain a 3-5ppm Cl- level and you should keep it clear.

Beyond that depending what type chemical feed system he has start the regular process. If its tablets, use the stabilized ones keeping check on the cyanuric to make sure you get a usable level but its never too high. If it gets too high, either switch to the non stabilized tablets or use liquid Cl- for awhile.

Have him buy a Taylor test kit. It will test everything you need to know about your pool without trips to the pool store.
Aug. 5, 2008 7:29 a.m. littleturquoiseb Reader

how to clear a green pool video
Aug. 5, 2008 8:18 a.m. carguy123 HalfDork

I had the same prob a few years back. Super cholorinating didn't alleviate the problem but it did etch the plaster. They make a product called NoPhos that gets rid of the phospates in the water that feed the algae. It works wonders!

You apply it to the filter intake and it neutralizes the phosphates that get into the pool water. You reapply it when you clean the filter.
Aug. 5, 2008 9:59 a.m. racerdave600 Reader

The problem could definitely be in the filter. To say it never goes bad is incorrect. The alge can make a nice home in there, and no matter what you do chemical wise, it won't be enough, it can get clumped and embedded.

Sand is pretty much one of the worst medium for pools, even though the sales people will tell you otherwise. Sand rounds off and ceases to filter correctly. Tell him to open up the filter and change the sand, but not before vaccuming to waste all the alge he can see in the pool. He'll need to put a hose in the pool at the same time as he'll be emptying the water as he does this. Also, make sure his ph and total alkalinity are in line, as these too can have an effect in alge removal.

Lastly, there are different kinds of alge treatments, shop around and ask a lot of questions. Shock the living crap out of it, balance the water, use the algecide, and never turn the filter off. If it doesn't have a bottom drain, put the vaccum hose in the center instead of using the skimmer to pull the water. The pool needs circulation and pools without main drains are especially prone to repeat alge attacks.
Aug. 5, 2008 10:35 a.m. oldschoolimport New Reader

I've had to help take care of my parents pool since I was a kid, and I hated it. when I got married, I made it clear that if we found a house with a pool, I'd have dump trucks lined up the day that we took possession.

good luck, and I'm glad its not me...
Aug. 5, 2008 11:55 a.m. DILYSI Dave SuperDork
1. Make sure he's backwashing the filter. There is filter cleaner that you can add to the filter and let it sit for an hour before backwashing. It really releases the nasty E36 M3.
2. Get a good pool supply store and have them test the water. Ours can generally get our water clear in 1-2 visits within a week. They are good about giving specific instructions and not over-doing the chemicals.
3. We had really good luck with algea using some copper based chemical. went from a cloudy pool to a clear pool with lots of debris on the bottom in a day or so. Vaccum up the micro-corpses, and be done.