Okay so I recently got some goldfish and they died due to ph level being too high (too alkaline)...so I've started again and followed ever thing to a tea and i now have two tanks about 38L and 48L with two fish in each. One tank keeps going quite acidic within a day of adjusting the ph back to 7, whereas the other tank keeps going alkaline..we aren't doing anything different in each tank. Help?
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