New Pool Owners

[kirby]

We bought a house that had been foreclosed on and sat for about 1.5 years. It has an above ground pool we want to get going. We have been to the pool store multiple times, with the last visit telling us to drain the pool, clean and refill. We did this and our pool looks worse than before. We had it almost clear, it was just cloudy. Now our pool is green, and we cannot "shock" it out of it.

Our pool is: 33' above ground approximately 21,000 gallons.
We have a sand filter and 1.5 horse pump.

We read quite a few threads on this site before signing up, so we already threw away our test strips, and bought a six way tester from walmart with drops. We will use this until our other tester that was recommended comes in.

Our test show,

PH 7.2
CYA 55 PPM
CL .5
Br 1
AL 140

We already went to the store, and bought bleach, 6%, borax, and baking soda. We also have muratic acid on hand.

We are really tired of the "lets try this chemical" game, and would like to learn how to actually control our pool.

Can someone please help us?

[aylad]

Hi, and welcome to the forum!!

First off, when you drained and refilled the pool, did you add any CYA? Was it a complete drain? If you haven't added any, then your CYA should be zero--but if your pool is green, you might be getting a false result since the test works on turbidity of the water. Also, you don't have any bromine in the pool, so you can ignore that scale. That leaves...pH 7.2, which is fine, alk of 140, which is fine for now, and Cl of 0.5--which needs to come up in order to clear the pool. Do you have a working presure gauge on your filter? If not, you're gonna need one through this process.

So...assuming zero CYA (correct me if that's not right!), you need to shock the pool to 12-15 ppm and HOLD IT THERE as consistently as possible. This will require multiple bleach additions throughout the day. At first the chlorine will be used up pretty quickly, but as the algae dies, you'll see it holding for longer periods of time. In a 21K gallon pool, it will take 4.2 gallons of 6% bleach to raise the chlorine from 0 to 12 ppm...5.2 gallons if you want to go to 15 ppm. Afterward, each .5 gallons of bleach will raise your chlorine by about 1.4 ppm, so you can use that a guide to figure out how much more to add to get back up to the 12-15 ppm mark. For now, you can force your test kit to read higher chlorine levels than it's designed for using these steps http://www.poolforum.com/pf2/showthread.php?10073-Testing-high-chlorine-levels-(without-a-good-testkit) You're going to need to keep your chlorine at this level until the algae dies, the pool goes blue, and you're able to test at night after the sun is off the pool and again in the morning before it hits the pool, and lose 1 ppm or less of chlorine in that time. Then you can let the chlorine drift back down to the appropriate level for your CYA (see the "best guess chart" link in my sig for more info on that--you may have to log out in order to read it until your registration is upgraded).

Keep your pump and filter running during this process, keeping an eye on your filter pressure and backwashing when it rises 8-10 psi over your "clean" pressure.

This will help you get started. Congratulations on doing your homework and getting the new test kits--they will make your pool life LOTS easier!!

[kirby]

Lets see if i can keep this in order.

We added 6 lbs of stabilizer after the drain, (the "pool store" directed us). The drain was not complete, we had roughly 1.5feet of water left.

We have a working pressure gauge, so we will backwash as directed.

I will add the required 5.2 gallons tonight, and test in the morning to adjust back up.

Thank you for the help.

[PoolDoc]

It's much easier to answer your questions, when we have the details about your pool in one place. So, please complete our new Pool Chart form -- it takes about 30 seconds, but will save much more than that.
Pool Chart Entry Form (http://goo.gl/cNPUO)
Pool Chart Results (http://goo.gl/PXaLu)

Meanwhile, as long as you keep adequate chlorine in the pool (right now, that means 2 gallons of PLAIN 6% bleach in the pool EACH evening) and do not have metals in your pool water (from wells or trucked water, usually), you should be able to gradually move toward easy pool operations with no problems.