Help - I'm trying not to drain pool - high alkalinity, high calicum hardness

[cheri]

Hello,

I was here last month, trying to get rid of some stains on the walls. I'm still working on those with perpetual scrubbing. But I feel like a key to this solution is to lower my alkanity and calcium hardness.

Here are my numbers (Side note - I ran out of bleach yesterday, so my chlorine is currently at zero. Plan to get some tonight):

PH- 7.5
CC- 0
CYA- 45
CH- 800
TA- 180

I have been adding muriatic acid and my instinct is to add more. I also have a hose set up, so I've created some aeration. But I'm starting to feel like I'm going to have to hire someone to drain the pool to get down that CH. I read about "FLOC" but my pool is not cloudy at all. It is crystal clear. I just know that CH is supposed to be much lower.

I tested the hose water and it is 250 CH.

Is there anything else I can do other than partially draining the pool? If the water is clear, would that FLOC stuff work?

 

[mknauss]

Never use Floc. It can make a mess and you do not need it.

Calcium can only be removed from your water by taking the water with it out of the pool and replacing it with lower CH water. Or you can hire a Reverse Osmosis company to remove the solids (calcium, salt , CYA) from the pool. The pool must be algae free to do RO.

 

[Richard320]

You will never get your CH down to recommended levels with that fill water. Even if you replaced it all, you'd soon be out of range due to evaporation and refill.

A pool with 800 CH is not so hard to maintain. but higher than that gets a lot harder, so yes, you do need to replace some water or hire someone to do reverse osmosis, if it's even available.

It's fairly simple math, especially if you figure out your average depth.

(% old * 800) + (% new *250) = new CH.

The % is done as a decimal. 80% = .80

If you know the depth it's easy to figure how much to drain to hit a target. For simplicity, let's say the pool is an average 50" deep. If you replace 4" of water, that's 8% or .08. 4 divided by 50 = .08. Easy.

Then just plug it in. (.92 * 800) + (.08 * 250) = 736 + 20 = 756 CH

Or if you remember your algebra (that you swore you'd never ever need once you graduated) you can figure out how much to exchange to reach a target.

Let X = percent water to replace

((1-X) * 800) + (X * 250) = target.

You want 600 CH?
((1-X) 800) + (X *250) =600
800-800X + 250X = 600
800 -550X =600
800-600 =550X
200 = 550X
200/550 =X
.3636 = X

So if the pool is 50" deep, you need to drain and refill 18.18 inches of water.

And then once the CH is down, you will need to really work on the TA. Get it down to 60 or 70.

 

[cheri]

Thanks everyone. I guess I'll start looking into how to drain it or pay someone to do it.

The pool is 5 feet at the deepest and it is closer to 4 feet. And then I have a hot tub that is only 3 feet. So, when we average it all out, 4 feet sounds fair. So, 18 to 20 inches sounds right.

One more quick question - If I were to try to drain it myself, can a 20 x 30 foot lawn absorb that much water? I don't have a hose long enough to make it to the street.

 

[Richard320]

Thanks everyone. I guess I'll start looking into how to drain it or pay someone to do it.

The pool is 5 feet at the deepest and it is closer to 4 feet. And then I have a hot tub that is only 3 feet. So, when we average it all out, 4 feet sounds fair. So, 18 to 20 inches sounds right.

One more quick question - If I were to try to drain it myself, can a 20 x 30 foot lawn absorb that much water? I don't have a hose long enough to make it to the street.

Not all at once.

I've been known to run a few thousand gallons into my drain cleanout and flush out the pipes. My kitchen is at the back of the house, so the cleanout is right there by the patio. It couldn't be done with a backwash hose, though. Too much too fast. My setup has a hose faucet in the return so I can bleed off water whenever the pump is on.