Thanks and a quick question about CYA

mehmann

New member
May 14, 2009
3
Spring,Texas
Found this site trying to find out how to beat black algae and I think now that I have switched to the BBB method 2 weeks ago, major progress has been made. So big thanks for that! Before switching I was using the HTH Dual Action 3" Tablets in an automatic chlorinator. No matter how hard I tried, I couldn't keep the pool looking nice. After running some tests with the 6 way test kit I grabbed at walmart, I found I had almost no CYA in the pool. So thats were my question lies. I have been using those tablets for the two years I have owned the house, and only bought them as thats what the PO recommended. I would have thought from what I read here the CYA would have been through the roof. So my question is "Where did all the CYA go?"

Thanks again for all the help again,

Mike
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
Welcome to TFP!

CYA can sometimes all disappear over the winter. You can't count on that happening, but it does happen fairly often. Since it is relatively early in the season, it could still be low from having gone to zero over the winter.

Another possibility is that you have a very high rate of water replacement. That is most likely to happen if you have an autofill system and a leak, so that water is constantly being replaced.
 

mehmann

New member
May 14, 2009
3
Spring,Texas
Thanks Jason. Forgot to put my location in my profile... Its actually been pool season for about 2 months already for us down south here :-D I don't have an auto fill but I have always had to add water about once every 10 days or so. Also I don't really shut the pool down over winter. It rarely gets below freezing here so I just turn my pump timer down to about an hour a day just to keep some circulation going. When I was first getting beat by the black algae, I think I dumped probably 10-15 lbs HTH Super Shock and swim trying to fix it, but I don't think that has any CYA in it to affect things.

Thanks again
 

Tbell

Well-known member
Jun 20, 2010
138
Tennessee
Mike...Might I just add a suggestion? I had been using those tabs and strips as well. The strips were showing that my stabilizer was low. Have you added any stabilizer...and if so how much? I added 18 gallons of stabilizer to my pool and then came here and found out that you can get a 0 reading when you actually have too much stabilizer. I went and had my water tested at the pool store and my stabilizer (CYA) was at 184. Your pool will eat Chlorine in large amounts when CYA is this high and it will make your PH drop as well! Please get one of the test kits they have available for you here and have your water tested at a pool store while you are waiting. I had to drain over half of my 30' pool and refill because once the CYA is in there it doesn't come out! Please just make sure that you don't have too much stabilizer....it is in the 3" tabs and shocking products as well and builds up in your water. Good luck!
 

mehmann

New member
May 14, 2009
3
Spring,Texas
Tbell
Not sure what strips your are talking about. I got the WM test kits with the drops and vials and such. I know I need a better kit, just not in the budget right now. I had the pool store test it before I bought it though and they said my CYA was at 30. The good range on there test though was 35 to 200 which from reading i know cant be good. I have added some more stabilizer (3lbs disolving as I type) and it seems to working better now. I am adding just a little bleach every few days and it seems to be holding right at 3. What little is left of the black algae is slowly but surely going away.

Thanks for the suggestion
 

Tbell

Well-known member
Jun 20, 2010
138
Tennessee
Great! I was not using the drops...was using the6 way strips you dip in the water . I thought that was hat you meant you were using. I just don't want anyone to have go through what i just had to. I might add that I am obviously an idiot when it comes to pool chemistry! LOL! I have had my pool for 10 years and have learned more off this board in a week than I ever knew.