Can't get FC level and water is cloudy.

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SinistrV6

SinistrV6

0
Sep 6, 2008
140
Mississippi
Pump died over the winter and I let the pool go. Had a heavy algae build up (pool was green/black). Over the course of the last 3 weeks I've put in:

15# of CYA (in a sock through the skimmer)
30 bottles (182oz) 6% bleach
2 full bottles of clarifier
4# of "shock"

Today my numbers are:
pH- 7.3
FC - 0
CYA - 30 (first time it's registered AT ALL)
TA - 100

Water is still VERY cloudy and has what I assume is the dead algae (turned white) on the bottom.

Am I on the right track or do I need to "back up and punt"?

BTW, How often and for how long should I backwash the filter?
 
sounds like your CYA converted to ammonia over the offseason. Make sure you can rely on your testing and get ready to keep adding bleach...although liquid 12.5% would proabably help you lug less weight around
 
It sounds like things are going well, but it is difficult to know without more information.

The most reliable way to tell how you are doing against algae is to do an overnight FC loss test. There is an article in Pool School about it if you aren't familiar.

The filter should be backwashed any time the pressure goes up by about 6 psi. You normally backwash till the water comes out clear, typically a couple of minutes but it varies.

I wouldn't bother with the clarifier. That is really designed for a different situation entirely.
 
There really isn't any way to tell from the information you have given us. You need to do an overnight FC loss test to see if you have actually killed the algae or not. If there is still living algae then there is likely to be one set of problems. If the algae is dead then there is likely to be an entirely different set of problems.
 
OK, after a couple more days of working on it, I'm finally getting somewhere.

Yesterday (late afternoon) my FC was 20. This morning at 0700 it was still at 19!

CYA is now at 70

Here are the full results:

pH - 7.3 (may not be accurate at this FC level)
FC - 19
CC - .5
CYA - 70
TA - 140 (an increase of about 30)
CH - 10 (I only ran this one because I'd read that high CH levels can cause cloudiness)

Now that I've got CYA and FC levels back in line, what should I do about the cloudiness? It's VERY cloudy (you can just barely see the water return "eyeballs" on the walls.)
 
High chlorine levels cause the pH test to read falsely high, so I'd actually be concerned that the test result is at 7.3, which indicates that it could be much lower, making acidic water. In that case, the cloudiness could be from the water eating away at something, although it would have to be low for a long time to get that cloudy.

Was the sun still on the pool when you measured 20 in the FC test?
 
I wouldn't worry about the PH for now - the cloudiness can take up to a week to clear after a bad algae situation, sand just takes longer.

I suggest you keep it at shock level for one more night, repeat the overnight test. If it holds again, the algae is dead and just give it some patience.

Some pools take longer to clear than others. My friends pool (I just helped them clear their swamp) cleared 2 days after the Overnight test. Another thread on here - she waited over a week and it didn't clear so she used a clarifyer.

I wouldn't try a clarifyer until you have waited several days to a week - you should see visible improvement each day. If you are not, please post back and lets us know.
 
I wouldn't worry too much about PH right now. The PH might be a little low, but it isn't going to be way wildly low. (The FC level isn't high enough to cause that kind of wildly wrong reading.)

You are still losing chlorine overnight, so it isn't time to be worried about the water being cloudy just yet. The cloudiness should start getting less cloudy day by day beginning when you are no longer losing FC overnight. You should double check the filter and make sure it is working correctly and you are backwashing/cleaning the filter often enough, just to be through.
 

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baudilus said:
High chlorine levels cause the pH test to read falsely high, so I'd actually be concerned that the test result is at 7.3, which indicates that it could be much lower, making acidic water. In that case, the cloudiness could be from the water eating away at something, although it would have to be low for a long time to get that cloudy.

Was the sun still on the pool when you measured 20 in the FC test?
Click to expand...


Yes, there were still about 2 hours of sun left when I got the 20. So a drop to 19 overnight didn't alarm me much. Wanted to test after nightfall but had to go to work.
 
I'm backwashing about twice a day. The pressure on my filter never changes very much. I replaced the gauge with a higher quality one recently and it stays around 17.5 pounds when it's in operation. Drops to about 10# when backwashing.

How can you tell if your sand filter is/isn't working properly?
 
Yes, backwashing more frequently when fighting algae, or possible algae, is very good. At the same time it is easy to over do it. Sand filters need to be "a little dirty" to catch smaller particles. You can get that little bit dirty by adding DE or by allowing some actual dirt to accumulate in the filter.

In this particular situation is is quite possible that most of what is clouding up the water is stuff that can pass through a clean sand filter. It sounds like a good moment to try something different, especially since it has been a while without improvement, so let the filter go for up to a week and see what happens. If you are at all inclined to, this would also be a good time to try out some DE in the filter. You still need to check the filter pressure frequently. If this whole theory is correct, and it does start catching the stuff in the water, the pressure might suddenly start going up rapidly.
 
Update:

My FC and CYA numbers still look good but the water stayed cloudy all week. So yesterday morning I bought some DE and added it according to the instructions on the box (1# dissolved in 2 gallons of water, then added to the skimmer). I saw about a 1 psi rise on my sand filter but it didn't last very long so I repeated with the DE and got about a 7 psi rise that lasted the rest of the day. The pump shut off last night (forgot to override the program) and when it came up this morning my filter pressure is back to it's original reading (about 18.5 psi).

Additionally, I don't see much change in the water clarity. Is this, perhaps, indicitive of a filter issue?

Any input is, as always, appreciated.
 
When you are fighting algae you need to hit it hard, fast and consistently. If you slow down, it will not, so you could start losing ground. Your pump needs to be running 24/7 until this thing clears.
What is your FC loss overnight now?
 
whoozer said:
When you are fighting algae you need to hit it hard, fast and consistently. If you slow down, it will not, so you could start losing ground. Your pump needs to be running 24/7 until this thing clears.
What is your FC loss overnight now?
Click to expand...


No longer having FC loss overnight. Pump is back in around-the-clock operation.
 
To recap: You are done shocking (0.5 CC or less and overnight FC test shows loss of 1 ppm or less), right?

Your pool is still cloudy and you do not see any improvement, even after adding the DE?

You might consider giving the filter a good cleaning just to make sure there are no issues inside.

waterbear actually recommends doing this once a year. Here's a link: my-sand-is-channeled-how-to-fix-it-t7626.html

Please add more info on your filter and pump in your sig. It could be helpful for the responders.

If you post a full set of test results, folks can take a look for you to help make sure nothing else is going on.

Can we see a pic? :)
 

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