Suspect Black and Mustard Algae


Silver Supporter
Apr 9, 2019
Pool Size
Liquid Chlorine
Hello, so I've been keeping a good amount of 1 gallon LC on hand due to the difficulty finding it at the local stores. I keep the LC bottles in a plastic container behind my garage, where it's mostly shady but in the evening may get some sun.

Over the past three days, I noticed my FC levels dropping fast and remaining low. This morning the same occurred when testing. My FC was 4 and I just added 109oz the evening before based on the previous day's reading and poolmath. This morning when I grabbed a new bottle of LC, I noticed the color was no longer the yellow it usually is, and it looked almost clear, like water. I didn't pay attention to the previous other bottles I had poured in the days prior. The bottles in question were about 3-4 weeks old, maybe longer. I am guessing the 10% strength has decreased to almost nothing since the color changed and I am also guessing this is why my FC level is remaining low.

I have about two bottles of the older batch left, should I continue to use the older LC or start with a new batch.

Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread