the darkman

Hello i have little black bugs in my water pool, i think they came from my rockwell, the bugs aren't on my plants but i see them in the water, some are alive but the majority drown, what can i do before they get to my plants. or do u think they are mites
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Hello i have little black bugs in my water pool, i think they came from my rockwell, the bugs aren't on my plants but i see them in the water, some are alive but the majority drown, what can i do before they get to my plants.