Algae question

[jcdifi26]

This is my second year with this pool. First year I used the standard pool store stuff: shock, pucks, etc.. All was OK the first year, but I always had an algae problem. I would shock and it would disappear for about a week, but it always came back. I opened the pool 3 weeks ago. It was totally clear from what I used to winterize. I started with the BBB method this year. After 2 weeks everything was great. I put a solar cover on. I have not been in the pool yet due to in-climate weather. I have been checking daily and my levels are:
Chlorine - 3 to 3.5
Free Chlorine - 0
PH - 7.5
Alkalinity - 100

I run the pump 4-5 hours a day.

When I pulled the solar cover off today I had a pretty good amount of algae on the bottom. I vacuumed, added more chlorine and I am currently running the pump. It is clearing up fairly quickly.

I have not used the pool and the weather here has been cloudy and rainy. Is this normal?

Thanks

 

[tim5055]

No, it's not normal. The first question is what is your CYA level. FC should always be maintained in ration to CYA following this chart - [FC/CYA][/FC/CYA]

Without the CYA I don't know if you are too low on the FC, but I'm guessing you are.

 

[jcdifi26]

No, it's not normal. The first question is what is your CYA level. FC should always be maintained in ration to CYA following this chart - [FC/CYA][/FC/CYA]

Without the CYA I don't know if you are too low on the FC, but I'm guessing you are.

Thanks for your response. Looks like my CYA is 90. What do you suggest?

 

[tim5055]

There is your problem. With a CYA of 90 FC should never go below 7. The high CYA locks up the chlorine,,thus algae can grow. See [FC/CYA][/FC/CYA]

It is simple, you need to exchange water to get the CYA to a reasonable level and conduct the full SLAM Process process.

What test kit are you using?

 

[jcdifi26]

Taylor, I think it's a TF100, not sure tho. Tested again and it may be closer to 80. I'm going to take a sample to a pool store and have them test it. I'll report their results later. I had it tested last year at this time and CYA was zero. When I opened the pool there was no algae at all. However, as I stated before, I did have algae issues last year.

 

[tim5055]

Skip the pool store, we trust your number more than theirs.

 

[domct203]

Skip the pool store, we trust your number more than theirs.

+1

CYA is the one they most often get wrong.

Does your test kit contain a FAS/DPD chlorine test that uses a powder to turn the sample pink, then drops to measure FC? You posted "Chlorine 3-3.5 & FC 0", that would mean that CC = 3-3.5ppm, which suggests problems in the water.

Please post a complete set of test results including:
FC
CC
pH
TA
CH
CYA

 

[jcdifi26]

FC - 3-3.5
CC- 0
pH - 7.5
TA - 100
CYA - 80

I've never done a CH test, I have to see if it can be done with my kit. The chlorine test with the kit does not use powder. It's 5 drops of R1 then 5 drops of R2. That's FC, then add 5 drops of R3 to get CC. (Not sure what's in the "R" bottles). According to the pool math calculator I would have to drain 50% of my pool at 80 CYA. Does this sound right?

Thanks

 

[tim5055]

FC - 3-3.5
CC- 0
pH - 7.5
TA - 100
CYA - 80

I've never done a CH test, I have to see if it can be done with my kit. The chlorine test with the kit does not use powder. It's 5 drops of R1 then 5 drops of R2. That's FC, then add 5 drops of R3 to get CC. (Not sure what's in the "R" bottles). According to the pool math calculator I would have to drain 50% of my pool at 80 CYA. Does this sound right?

Thanks

Is your kit in a big blue box? If so you have a K-2005, not the TF-100. The TF-100 comes in a clear tackle box, but there is a smaller blue box inside.

Yes, if your CYA is 80 and you want it at 40 you have to drain 50% of the pool.