JKM - I was not suggesting that you add copper sulfate or any copper based chemicals to your pond to treat the P.parvum. I just mentioned it to indicate that these guys are very sensitive to copper based products. Also when P.parvum is collected for analysis one has to be very careful how it is preserved due to the organism's delicate nature. I am concluding that based on their highly sensitive nature, they are likley going to be sensitive to leachates from barley straw.

Your very high alkalinity is why P.parvum grows in your pond.


aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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