Green pool

[lande]

We had a leak in our pool. Finally quit at the light. Leak repaired. Filled swampy, green pool with city water. Cleaned all filters. Adding Stabilizer in sock in the skimmer. CYA is 0. Having to backwash every 2-3 hours. Please help!

[lande]

I asked a question but did not see how or where to put my signature info. I just received my new TF 100 test kit. The results are: chlorine 0, Ph 8.2+ TA 150, CH -0 CYA - 0

I am concerned about running pumps 24/7 when the psi goes up 10 points every 2-3 hours.

Signature:
24K gal, IG, fiberglass,Hayward DE 4820, GPM96, 1 HP 2 speed Whisperflo pump, Pool built over 30 years ago (plaster) Resurfaced 7or8 years ago with fiberglass, Polaris 180

[PoolDoc]

Not sure why you are having to backwash -- is the water still green?

Regardless, do this:

1. Add daily 2 gallons of PLAIN household 8% bleach to the pool, for each 10,000 gallons. Add the bleach in the late evening.

2. Purchase a cheap OTO test kit (yellow / red drops) and test the chlorine level in the AM, after dosing the night before. Test the pH & chlorine again in the PM. Post results here.

3. Tell us about your pool: size, gallons, type of filter.

[PoolDoc]

You posted while I did.

Ok. Read the muriatic acid guide, also in the blue signature bar. Purchase a gallon, and use it -- safely - you DID read the page, RIGHT? -- to lower the pH.

Add the bleach as previously instructed -- 4 gallons each evening. Ideally, do so THIS evening.

Let the pump run on low speed at night. However, if you add the bleach via the skimmer ( NO other chemicals in the skimmer!!) it will likely help the filter. Sounds like you still have algae growing. Live algae stops DE filters up FAST.

Actually since you have a concrete pool, and seem to have algae, make your FIRST dose 8 gallons -- around 20 ppm of chlorine. With a CYA of 0, that should kill all growing algae overnight. But till you have CYA in the pool, you'll need to continue to dose each evening.

Once the algae is all gone, and there are no more filter problems, you can drop back to 2 gallons per night.

Once you have the algae dead, the pH down, and the pool running reasonably well, re-test all parameters and report back.

[lande]

Thank you so much. Will get started with the acid and yes, I did read. One correction. In your last post you said we had a concrete pool. We do not. It was originally plaster and then resurfaced with fiberglass several years ago. Thanks again for your help.

[PoolDoc]

You're welcome.

[lande]

Things are looking up. The pool is no longer emerald green but much a much lighter shade. It is still cloudy. This AM the values were: CYA 50, FC 8.5, CC1.0, TA 130 and Ph 7.5. I have had to add some more water to the pool because of the backwashing.

Shall I still put in the 4 gal. of chlorine this evening? I have some Super Shock (Kem Tek) Trichloro - s- triazinetrione that I had before I joined BBB. Can I use any of that?

When using the pool calculator, how can I tweek it to tell me shock levels of chlorine and not just maintenance levels?

Thank you for your help.

[PoolDoc]

If it's still green, add the 4 gallons. Chlorine won't clear water made cloudy by dead algae -- you have to filter OR settle & vacuum for that. But chlorine will kill algae, turning green to gray or brown.

[lande]

THINGS ARE IMPROVING!! We can see the bottom at the shallow end and we can see the light in the deep end. The water in the deep end is still green but a much lighter shade. We have been testing 2X day, using the pool calculator and brushing frequently. I do have a concern. There is a green line all the way around the pool at the level of the top of the light. The swamp water was at that level for at least a week while we waited to see if the repair to the leak at the light actually did the job. My concern now is that the fiberglass is rough from that line down into the pool. The hose of the polaris and the polaris itself is coated with a rough grey green substance. Have we ruined the fiberglass finish?? Is this scale?

This mornings readings: FC 10.5, CC 1.0, Ph 7.5, TA 140 CYA 40

[PoolDoc]

It sounds like you have something that I've called "sand algae" -- under certain conditions, algae can build tiny calcium domes over itself. When the algae is dead, the scale remains. You can check it this way:

1. Remove the Polaris from the pool.
2. Fill a 3 - 5 gallon bucket with 1/2 gallon of bleach + 1 gallon water.
3. Put a section of hose in the bucket, so the green scale is immersed in the bleach solution. You don't need to remove the hose to do this; just fold a section into a 'U' and put it in. Set something on the hose, to hold it in place for an hour.
4. Remove the hose, and pour the bleach into the pool. Rinse the hose with fresh water and then inspect: if it's sand algae, the scale will remain, but will be tan to brown, instead of green.
5. If it appears to be sand algae, continue to step 6. Otherwise, report what you found here.
6. Rinse the bucket out, and fill it with 1.5 gallons of water. Add 1/2 gallon of muriatic acid. Put the bleached section of the hose in the acid solution; wait 5 minutes. Remove and rinse. The scale should be gone. Pour acid solution into pool.

CAUTIONS:

1. The bleach solution will damage clothes instantly, and eyes quickly: wear old clothes and safety glasses, or at least, sunglasses. Have a hose ALREADY RUNNING a small stream of fresh water, nearby. Rinse spills promptly.

2. Muriatic acid fumes and damages eyes, and can burn skin. You need glasses and gloves (kitchen gloves are fine). Once it's diluted, it will stop fuming. READ THE MURIATIC ACID PAGE, linked in my signature.

NOTE:

1. You need to report pH, alkalinity AND . . . calcium levels. If this is sand algae, you'll need to manage those levels differently.