Just a thought. Try checking your
Kh. If it is below 6 then you may be subject to acid crashes. I add bicarbonate of soda to bring my tap water (
Kh 0-1) up to 6. My Ph is stable despite the best efforts of my
Co2 injection to drop it. It's cheap and effective. I find 2.5 ml of bicarb to 10l water does the trick, but add it to your regular WCs and not direct into the tank, the Ph may rise too dramatically otherwise.
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