When you moved the tank did you use the same sand?
It is possible that if the sand bed was disturbed that you could be having a bacterial die off and that might disturbed the
ph enough that the seaclone you have might not be cleaning up the tank or adding enough O2 to keep the tank stable.
How long after the move has the
ph remained low and how low is it?
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believe nothing, no matter where you read it or who has said it, not even if I have said it, unless it agrees with your own reason and your own common sense.........(buddha)