Very green pool

[jmac31]

Hello everyone,

Since we purchased our house I have been working on this pool daily. It has probably been a little over 3 weeks of constant work on it, chlorine, scrubbing, raking, etc. The pool is still green and I still can't see the bottom.

I purchased a test kit and have been testing the water and getting my levels to where I need them. I took a sample into our local pool store and they had quite a few different readings than what I got.

Pool Store:

FC = 3
TC = 5
PH = 8.0
TA = 140
CYA = 100
CH = 170
TDS = 850

He didn't test metals like I asked, so will be going back but somewhere else this time. Anyways here is what I have for my readings.

FC = 19
CC = 1
TC = 20 ???
PH = 7.7
TA = 160
CYA = 65
CH = 180
TDS = ?

We are currently shocking the pool like crazy, which is why his FC of 3 is very weird. We took our reading about 1 hour after we took in the sample in to the store. We had shocked before we took the sample in to the store. This will be day 4 for us of keeping the FC >= 20, and the pool is still not clearing at all.

I see that our CYA is a bit high which is odd, because we filled the pool about 3 weeks ago, it was about half full.

It is a 25,000 gallon vinyl lined pool. We are currently using bleach as our form of shock. Any help would be greatly appreciated.

[aylad]

Hi!!

If your test kit is a drop-based test kit, then I would trust your numbers over the pool store. If you had shocked the pool right before you pulled the sample for them, and delivered it fairly quickly, then their numbers don't make sense at all.

With a CYA of 65, 20 ppm is the minimum that you want the chlorine to be, in order to attain shock level. At CYA of 100, then 25 ppm is the minimum. Have you been reaching 20 ppm and then holding it there, which is what you need to do, or have you been letting it drop? A common mistake that people make is to shock the pool and then let the chlorine drift right back down again, which really doesn't help the situation. Shocking means to elevate the chlorine to the recommended level (based on your CYA ) and then holding it there until the problem is gone.

I would check your chlorine tonight, after the sun is off the pool, and then check it again in the morning. If you're losing chlorine during that period of time, then you just need to keep up the chlorine, and possibly even bump it up a little to 25 ppm. If you don't lose any chlorine during that time, then we need to look at something else that may be causing your green, because if it's algae, it'll be eating chlorine.

What type and size of pump and filter do you have? Is your test kit a DPD-FAS (uses drops), or DPD (uses tablets)? Have you ever used trichlor tabs in the pool? If so, did they contain copper, and what was your closing CYA level before winter?

Janet

[jmac31]

Hey thanks for the reply!

We had reached 25ppm a couple nights ago, when we got up in t he morning it had dropped to about 17ppm if i remember correctly. We have been checking the levels 3 times a day and raising them back up if the drop. We can't check the levels more than that so it does drop down. I'm thinking maybe we should get our ppm up to about 30 and see what happens tonight. I'll let you know our readings tomorrow morning.

We have a 3/4 hp 1.27 sp Pentair Challenger pump and a Sta-Rite HRPB24 filter. The filter is quite large, 250lb is my guess. Yeah we purchased a DPD-FAS test kit, the Taylor K-2006. When we first shocked the pool we used sodium dichloro-s-triazinetrione, which from my understanding adds to the CYA, just didn't think it would add that much. We did not own the house when it was winterized so I am unsure of the CYA. Here is the post I originally made about the pool, it was in really bad shape http://www.poolforum.com/pf2/showthr...ol-need-advice.

[jmac31]

Quick update, got the ppm up to 30 and planned on keeping it there. We got some pretty heavy storms here tonight and I didn't get a chance to make it out there to put more chlorine in or check the levels.

On a side note, our impeller on the pump keeps getting clogged and I am pretty sure it is because of the filter basket floating up when it fills with water. I went out and bought a large 10" long bolt to place in it and weigh it down. This should be fine shouldn't it?

[madwil]

the bolt will temporarily be fine, but wouldn't use long term- once it starts to rust, will add iron to your water over time!
maybe use a divers baton for weight, or make a small weight with sand/PVC... gotta do the same thing myself!
keep working the chlorine- it'll clear your pool and it will all be worth it!

[aylad]

Or a rock............

Janet

[madwil]

duh... why didn't I think of that, with all this river rock and rose quartz laying around? lol... I can help others, but can't help myself!

[jmac31]

Good idea with the rock. It appears that the bearings in our pump are going out so we haven't been able to do much with the pool. Hopefully it will be fixed by tomorrow.

[jmac31]

Bad news about the pump, looks like the motor is going out. Can anyone recommend a good pump? It is a 25,000 gallon pool with a Sta-Rite HRPB24 filter. I'm pretty sure our plumbing is 1&1/2 inches if that helps any.

Thanks