Great strides made, but...

[spaige]

After a bout with algae this winter my water is looking significantly better now. However, there still seems to be a little cloudiness that I notice at night when the pool light is on and when my cleaner is running. I'm thinking maybe the cleaner is stirring up something, possibly dead algae? One suggestion had been that oversaturation of calcium carbonate was causing the cloudiness when my chlorine levels were really high; chlorine was close to 30 at one time. Currently my readings are as follows:

Chlorine 7.5
CYA 70
Ph 7.4
Alkalinity 90
Calcium 200

I have replaced a significant amount of water and as I did the water got clearer. Again, it has come a long way but I still think it can get clearer. Any suggestions would be appreciated.

Steve
Atlanta, GA

 

[JasonLion]

Your calcium saturation index is negative so calcium clouding isn't going to happen.

There are almost always some bits of dust that are visible at night when you have a pool light, even when the water is perfect. But they normally looks like individual motes of dust, not like clouding.

You might try adding a small amount of DE to your sand filter, that will improve things.

 

[dschlic1]

How much chlorine are you adding? Try and calculate the ppm daily dosage from your filter runtime, SWCG cycle time, SWCG max output and SWCG setting. In general if this is over 3 or 4 ppm per day you probably have an ongoing organic problem. Another way to test is to shut your SWCG off at dusk and test the chlorine level. Then test again the next morning at dawn. If you have lost more than 1 ppm FC you have an organic bloom.

 

[spaige]

Jason, how do I get the DE into the sand filter? Do I have to undo plumbing to do it or can it be added through the skimmer?

I don't think I have an organic bloom problem. It took weeks for my chlorine to get from around 30 to 7.5 and that was even with replacing a large part of the water. I haven't added chlorine for many weeks now. My water temp. is below 40 degrees as well.

 

[JasonLion]

You add the DE through the skimmer. First, note you current filter pressure. Mix about 1/2 cup of DE with water in a bucket and the pour that slowly through the skimmer (with the pump running, on high if you have a two speed pump). Give things 15 minutes to settle and check the filter pressure. If the filter pressure has gone up less than 1 PSI add another 1/2 cup of DE. The next time around you can add the full amount of DE that brought the filter pressure up 1 PSI all at once (still pouring slowly).

 

[spaige]

I've been reading that dead algae is hard to remove. Is there any truth to that?

If so, will the DE help or is draining and refilling my only option?

 

[JasonLion]

A sand filter can often take a week to remove dead algae and get the water clear again, sometimes more sometimes less. Large filters and lots of circulation speed up the process, so run the pump 24/7 until the water clears. There is nothing difficult about it, it just takes time and backwashing as needed. I would never drain and refill just because of algae. If you are in a hurry there are some other options, but they take work and cost money, all to save a couple of days.

Adding a little DE to the sand filter will speed up how long it takes for the water to clear and over time it will get cleaner than it ever would be with sand alone. But you do need to replace the DE every time you backwash.