Wanting to have an air line (no air stone, just air line) in the bottom of my autopot res to keep nutrients mixed. how would people would go about weighting their air lines so that they don't float to the top of the reservoir?. Currently threading it through a plastic bottle which is attached to a dumbell weight made of copper and iron (not good for the water surely) so need better, tidier, simpler ideas. I can't think of any, any help or ideas would be appreciated!
Cheers
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Cheers
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