Small CinderBlock Fell In Pool over Winter...

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.

Small CinderBlock Fell In Pool over Winter...

Postby Guest » Sat 26 May, 2007 15:51

Don't ask how, it's a long story.

Anyways I have this small 2x3 foot cinder block sitting at the bottom of my pool. When I uncovered the pool in the spring, I have a green mess, I'm talking BAD. I've probably spent about 100 bucks on treatments, chlorine shocks, etc from the pool store. Now the pool is a cloudy milky color. Not really green anymore though, just not clear like it used to be.

So, My wife reminded me that I have a small cement cinder block at the bottom. Is this going to affect anything? Do I wait for the water to clear and then take it out?

I'm a little sceptical to go under water to grab the block with all those chemicals in it. Plus I can't even see where it's at, because the pool is so cloudy.

I guess the question is will the cement block affect the time it takes for the pool to clear up? Were selling the house soon so I want it clear ASAP. Thanks,


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Postby Buggsw » Sat 26 May, 2007 16:42

It shouldn't affect the water. Get it out when it is clear and you feel safe to enter.

Keep your chlorine level at super shock level for 2 or 3 days and also adjust your PH if necessary. Run your pump 24/7 and backwash at least daily, if not more often. Vacuum the crud to waste, if you can.

Depending on your type of filter, the water should clear within 24 hours to 7 days. If it hasn't cleared by then, use a clarifier solution.

Postby Guest » Sat 26 May, 2007 17:33

My PH is sitting at about a 7.0.

Is that good?

It's a sand type filter. I've had the filter / pump on 24/7.

Should I add chlorine every night? I was reading that the cal hypo 65% was best to add every night. Is that correct?

Right now the water is a milky bluish color...maybe a hint of green. Thanks,

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Postby Buggsw » Sat 26 May, 2007 19:22

Yes, you need to raise your PH a bit. Depending on your TA, will depend on what you use to raise it. If this is a vinyl pool you need to get your shock up to 7.2 or above or it will damage the vinyl. If it's not vinyl, it's still too low, but definately worry about Chlorine first.

Don't use Cal Hypo. It could be the worst thing for your pool at this time. You need to post the rest of your readings to determine whether it is safe to use Cal Hypo. Same with any other type of dry shock, dichlor, trichlor. You may be introducing things to your pool like calcium, CYA, etc through these products that are lowering your PH and increasing your CYA - all sorts of stuff. The more CYA you have, the more chlorine it's going to take to shock.

The best would be to get liquid chlorine or regular store bleach (you need to use 2x the amount of store bleach). A gallon of liquid chlorine is 12.5% and a gallon of laundry bleach is only 5-6.5%. A gallon of liquid chlorine is equal to 1 lb of dry shock. Depending on your pool volume and CYA, it could take several gallons. It's cheaper than dry shock, usually, anyway.

Adding chlorine at night is usually best, but, depending on your situation and location - if you don't keep it at a high shock level for several days all through the day and night, you are defeating your purpose. You may need to add some during the day to keep the levels up.

Keep backwashing daily or a few times per day and running the filter 24/7 and keep that plain old chlorine up. Get your readings at least daily if not more often until you get back in balance, at least.

If you have a water feature - turn it on - it will help aerate the pool and bring your PH up, as well.

Get your readings and post here.

Postby Guest » Sun 27 May, 2007 14:22

I have a crappy hth water test thing so I can't give very detailed readings.

All I can give you is my PH is now 7.2
Alk mg/l is like 140ish.
The Chlorine meter is kind of goes from 0-5 (the more yellow the higher the number) and it's pretty yellow now, not sure if that's a good or bad thing.
Oh and the pool is above ground, I'd guess anywhere from 10k-15k gallons.

I added about a half gallon of bleach last night. And another gallon this much am I adding? And I just poured it in straight, right next to the skimming basket. Is this right?

Right now mid-day it looks milky/blue still. Still can't see the bottom of the pool, but I can see probably 1-2feet down (albiet pretty cloudly).

Postby Guest » Sun 27 May, 2007 18:12

Ok after reading some posts, I found some "shot glass" method to calculate the chlorine. It was sitting roughly at 3ppm.

After adding a gal of bleach about an hour ago, it's sitting at 9ppm. How high should I take it?

Water still blue and cloudy.
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Postby Buggsw » Sun 27 May, 2007 18:42

If you are using store bleach, 2 gallons is equal to one lb of shock.

Sounds like you are doing the best you can do. Your Alk is a little high, but you shouldn't let your ph go down any further with a vinyl pool or you will get permanent wrinkley puckers. Keep a close eye on this and raise it by aerating and/or add 20 mule team borax so your alk doesn't raise - or use 8oz of soda ash to raise it .2 ppm at a time (this will also raise your TA a little).

HTH test kit is fine to use for chlorine, ph and alk. Here is how to tell what your chlorine level is using an HTH test kit. Make a 50/50 mix of distilled water and pool water, put that in the test vial and run the test as instructed. Then if you get a color in the test range, multiply the result by 2.

If you still get an orange Over Max reading then change the dillution to 3 parts distilled to 1 part pool water. Multiply the result by 3. This should get you close. At least it will tell you if you're closer to 20PPM than 6PPM

I'm going to give you the quantity of chlorine to add based on 10K gallons to raise your chlorine 1 ppm.

Regular Clorox bleach 5.25% - 3 cups
Super/Ultra Clorox 6% - 2 cups + 5 ounces
Pool Store chlorine 10% - 1 cup + 5 ounces
Pool Store chlorine 12.5% - 1 cup + 2oz

So if you added 1 gallon to a 10K gallon pool:
Regular Clorox -- 5.2 ppm increase
Super Clorox -- 6ppm increase
Pool store 10% -- 10 ppm increase
Pool store 12.5% -- 12.5 ppm increase

Keep adding chlorine and brushing and backwashing - it will clear a little more every day. Once it's clear, keep it at shock level for another day or so.

Postby Guest » Sun 27 May, 2007 20:31

What is this water feature your talking about (aerating)? On my filter I have
Filter, Backwash, Waste, Recirculate, Rinse, and Closed.

What is this aerate feature your talking about?
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Postby Buggsw » Sun 27 May, 2007 20:56

Any water feature, water fall, fountain, anything that will create small droplets or bubbles.

Some pools have an aerating nozzle on the side of them that sprays water up and across the pool. Sometimes you can position one of your returns or jets upwards and it will help to bubble the water.

If you're covering your pool, leave the cover off.
Any splashing, air exposure, bubbler will raise pH.

Postby Guest » Thu 31 May, 2007 23:03

Update - it's been about 4 days later but the pool is definately clearing up. It's still "cloudy" but I can actually see the bottom of the pool now.

Filter is being ran 24/7, daily brushing/vacuuming and backwashing.

The strange thing is I haven't really added any bleach since I shocked it that first day with about 3-4gallons. The chlorine level has stayed around 20-25ppm since then, no real drop.

However, keeping the PH is line is another story. Where do I get soda ash?

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