Green Pool

Information about pool

27,000 gallon
Sand Filter

So far pool was opened and looked pretty good, clear, minor debris in bottom that was vacummed up, added bleach to get clorine levels to a good amout

Check all chem levels using test kit and everything was fine.

Then I went out of town for a week and with the increase in temps the pool has turned green

Had a timer on pump to turn on for 4 hours a day.

Now status

FC shows level in the 20ppm range
CYA close to 100
PH is 7.2

Added bleach on Monday afternoon to bring level up to 20ppm range, 6 gallons total of 6% bleach from Wal Mart

Been brushing pool walls and bottom and backwashing several times a day.

Pump has been running 24 hours.

Green color has moved a little from a real dark green to a light shade of green

What should I do now?

Thanks

Hi Jay;

Sounds like you are doing enough, now. However with CYA ~= 100, you might want to take the chlorine a little higher.

Other than that, just stay on course.

However . . . when you get everything fixed, I'd recommend changing timer settings to a minimum (with a sand filter) of 4 + 4 hours spaced at least 6 hours apart. Service guy consensus seems to be that a single run of 4 hours is taking a risk of further problems. I know I would have thrown a hissy fit if any of my customers had tried to do that.

If you want to save more electrical $$'s than that, look into getting the smallest adequate pump in a two speed model, and running on low, except when cleaning.


Ben

OK update
Last night we had a bunch of high wind, filled pool with new leaves, spent some time skimming them and the pool skimmer was full.
So we got that cleared up and check the FC level, still over 20ppm, good
Brushed pool and backwashed filter
Went to bed

Today this morning check FC and it was near 15ppm, added bleach to bring it back up to 24ppm
Backwashed filter again
Added some water from hose to pool to bring level back to normal

Pool stills shows green color, but it might be getting slightly lighter.

Anything else I should be doing?

Make sure you are also running the pump 24/7. Keep an eye on your pH. You are ok at 7.2 but don't want it to go lower than 7.0.

Pump has been running constantly since Monday afternoon.

Color is still pretty green, when will the algae start to die?

Good thing the weather temps dropped over night, now my kids are not pestering me to get into the pool.

Are you consistently maintaining the high chlorine levels? Is your filter pressure rising?

Yes, if your FC yo-yos it takes much longer.

Is your pool vinyl or hard-sided? If it's vinyl, I would keep FC at 25ppm, not 20, and check it 3x/day. If it's concrete or plaster or something else hard, if it was me, I would take FC up to 30 or 35ppm and keep it there--won't damage a concrete pool but will bleach a vinyl liner. I'd really hammer the algae. But the decision is yours. Whether it's vinyl or concrete, I would at least take FC up to 25 instead of 20 and keep it there.

Carl

The liner is vinyl

Pool is starting to clear up going to a lighter green. Water is real cloudy

Keep brushing and working to keep FC at higher levels above 20.

I wonder if filter is not working properly, pressure gage does not seem to register properly. Any thought on that? I do have another pressure gage that I could replace.

A couple of years ago I replace the sand in the filter. Do I need to do anything different to sand, I did move it around to eliminate the channels that formed in the sand.

Thanks

Shouldn't need to do anything else to the sand, but if your pressure gauge is not working reliably, I would definitely change it out. Your filter may be too gunked up to do anything else until it's backwashed, but without the pressure gauge, you don't know for sure.

Edit for more info: If you do find that the pressure isn't rising, you can try to add a handful of DE (the type you use in DE filters) through your skimmer. It will help your filter catch some of the finer stuff. You need a working gauge to do that, though--you only want to add enough DE to raise your pressure by 1 ppm. That pressure rise can take up to 30 minutes or so, though, so if you add some, give it a little while before you add anymore. If the pressure gets too high, you'll need to backwash it out and try again.

Janet

Update
Today is Saturday and the FC checked in at 18 so I added a 1/2 bottle of bleach to bring it up to 22.

Pool is clearing slowly form dark green in the beginning to a light green in the deep end.

I have been brushing the pool a few times each day.

Bought a new pressure gage today , old one was shot.

Keeping pump running 24 hours a day,

Thanks for the tips