I remember reading a post on this forum about someone trying to get their pool cleared, only to find out that the wrong kind of sand was put in their sand filter. I'd say that was a rare case, but replacing your sand might be something to consider if you can't clear up your pool despite following all the advice given here.
Can't stop the algae
- Thread starter rshackleford
- Start date
At 9:00pm last night the chlorine was at 25, at 6:00pm this morning it had dropped to 19.5. I added another gallon of chlorine which brought me back up to 25. Going to keep it over 20 all day today and see where I sit tomorrow morning. The water is definitely clearer then it has been all summer.
Why was I passing the OCLT test last week with chlorine levels at 8? Just wondering why I wasn't oxidizing out chlorine at 8 when I know there was algae in the pool.
Why was I passing the OCLT test last week with chlorine levels at 8? Just wondering why I wasn't oxidizing out chlorine at 8 when I know there was algae in the pool.
In reality, you weren't. The OCLT is meant to do at SLAM levels. 1/8= 12.5% 5/25 = 20%. While 7.5% may seem like a large spread, but lack of consistency in drop size, as well as when you test this morning, could very well make up for the difference between your results and the generally accepted margin of error.
RS - what % chlorine are you using? even at 12%, a gallon should only raise the FC in your pool about 3ppm - you said you were at 19.5, added a gallon and got to 25, a gain of 5.5 - sounds like you may be experiencing some significant testing error, or your pool is not really 38K gallons
I'm using Liquid Pool shock from Leslie's which they say ranges between 10-12.5%. I thought that was a big jump as well. I'm going to go check it again in the next 30 mins just to be sure. I typically go up about 3ppm with a gallon. It was also early this morning and I'm questioning if it was one or two gallons now
My pool is 20'X40' with a 9'X12' kickout in the shallow end. IT is 3' deep in the shallow end and 9' in the deep end. So 20X40 @ 6' deep is 35,900 plus 9X12 @ 3' deep is 2400. I think that comes to 38,300.
if it normally goes up 3, and it may have been 2 gallons this morning, that makes sense - do you ever repeat your FC test? if you are curious you could run it twice on the same water sample - that would give you an idea of any testing error you may be seeing - and if you test samples from a couple areas around the pool collected at the same time, you will see whether or not it is well-distributed and even around the pool when you check it not long after adding
How handy are you? I would pop the lid off that sand filter and see what you got. On my 1st SLAM, the pool would not clear. I kept back-washing my filter thinking that was cleaning it. In fact, the filter bed had developed a condition called channeling, which pretty much bypasses the filtering capability. Oh yeah, the sand and gunk was disgusting. I can't believe I was running my pool water through the stuff. It was not hard to fix, just a garden hose and some elbow grease. I had to do it twice because I didn't do it thoroughly enough the first time. The second time I cleaned the sand with a sand cleaner product. It made a world of difference. Pool was clear 2 days later. My filter is loaded with Zeobrite so the process to clean the sand involves rock salt, otherwise the cleaning product is all you need. Good luck. I also refer to the TFP pros on here to correct any erroneous advice I may inadvertently give. I got one pool to take care of, so your mileage may vary.
Edit: Here is the cleaning procedure I used. I would omit the rock salt for regular sand:
https://www.dropbox.com/s/siz8e81444m8ytz/Zeobrite Regeneration.Bed Cleaner.Procedure.pdf?dl=0
Here is the deep, cleaning procedure: http://www.troublefreepool.com/threads/73192-Deep-Cleaning-a-Sand-Filter
Edit: Here is the cleaning procedure I used. I would omit the rock salt for regular sand:
https://www.dropbox.com/s/siz8e81444m8ytz/Zeobrite Regeneration.Bed Cleaner.Procedure.pdf?dl=0
Here is the deep, cleaning procedure: http://www.troublefreepool.com/threads/73192-Deep-Cleaning-a-Sand-Filter
I have pulled the top off the filter and stirred up the sand to make sure there was no channeling. It was actually pretty clean compared to some of the pics and comments from others on that thread.
I think I finally got rid of the algae. Water is perfectly clear and I passed the OCLT test last night. Thanks for all your help and good info.
I think I finally got rid of the algae. Water is perfectly clear and I passed the OCLT test last night. Thanks for all your help and good info.
!!
Congrats on getting your pool clear. What are you doing differently to keep it that way?