Found algae this morning

[scoobasteve1982]

Went out to my pool this morning to test and I noticed a little algae growing this morning at the bottom of the pool - mostly in the corners. Nothing major but was clearly algae. My pool is otherwise crystal clear and beautiful. Here's where I'm confused. My Taylor Test Kit K-2006 CYA test puts me at 30 or below. It doesn't test below 30. I've gotten pool store tests and they had me at 35ish but who knows if that's even accurate. For the past few weeks I've converted from Baqua and am now Baqua free (see this thread for that fiasco - Can't balance free chlorine - nothing is working). With all the partial drains and refills I got my CYA low again. I've been VERY regimented about testing my FC and CC - twice, once in the morning and once at night - and adding liquid chlorine as necessary to keep my FC PPM between 2 and 5ppm - trying for the high end. I've been noticing that with all the beautiful hot sunny days here (my pool gets sun ALL day) I've been losing 3 to 4ppm of FC every day - so I've been bumping it up every night. Last night I checked my FC (I had NO algea at this time - as far as I could see) and I was at 1.5ppm. So, I added a dose of liquid chlorine to get me back up at 5 to 6ppm. I did so successfully and tested this morning and was at 5ppm. My combine chlorine was at 0.5 or less - so that's good, however, the algae! Not sure what's going on there. After adding liquid chlorine I've been scrubbing too. Really confused about the algae when my CYA appears to be about right (30ish) and FC levels maintained and my CC low to almost 0. During my Baqua conversion and all the drain / refills I did test at the pool store and they said my phosphates were hight. However, reading here I found that if you maintain FC at adequate levels phosphates aren't an issue.

Really confused about the algae. Either way, this morning (cloudy and rainy here today) I shocked the pool to hopefully keep it at bay until I figure out what is going on.

Any insight is greatly appreciated! Thanks!

 

[Texas Splash]

Steve, we weren't supposed to hear back from you so soon. At least not for something like this. No worries. Here's what I suspect:
Your CYA was low to non-existent for the Baqua conversion. Once you completed the conversion, you were able to adjust and balance chemicals as needed. With a CYA of <30, it sounds as though your FC did not have adequate protection to defend FC from the sun's UV. You appeared to pass an OCLT and have no CCs but did visibly see algae, so I would definitely SLAM. Try to adjust your CYA to at least 30, adjust pH to 7.2-7.4,then increase FC to 12. Since your water is basically in good shape, it shouldn't take too long.

Now once you pass the SLAM (all 3 criteria), then you can consider increasing your CYA even higher. Start at 40, then 50 if needed to provide adequate protection or your FC and reduce FC loss during the day. Hope that helps. PS ~ Did you ever do that one last filter cleaning we spoke of after the conversion?

 

[scoobasteve1982]

Steve, we weren't supposed to hear back from you so soon. At least not for something like this. No worries. Here's what I suspect:
Your CYA was low to non-existent for the Baqua conversion. Once you completed the conversion, you were able to adjust and balance chemicals as needed. With a CYA of <30, it sounds as though your FC did not have adequate protection to defend FC from the sun's UV. You appeared to pass an OCLT and have no CCs but did visibly see algae, so I would definitely SLAM. Try to adjust your CYA to at least 30, adjust pH to 7.2-7.4,then increase FC to 12. Since your water is basically in good shape, it shouldn't take too long.

Now once you pass the SLAM (all 3 criteria), then you can consider increasing your CYA even higher. Start at 40, then 50 if needed to provide adequate protection or your FC and reduce FC loss during the day. Hope that helps. PS ~ Did you ever do that one last filter cleaning we spoke of after the conversion?

Thanks for your response Texas Splash. To answer your question, I did not clean the filter yet, unfortunately. Lots more going on this past weekend than I anticipated so I just haven't had time yet. But, I do plan to do so. Do you think this could be part of the issue?

My only question with regards to increasing the CYA - if my CYA test doesn't go lower than 30 how am I to figure out how much CYA I should add to get it to 30 without knowing an actual reading?