neworder 寫:
Hi fish-friends,
I bought a 'HYDOR' cannister filter 1/2 year ago. Now the water
flow is very very weak. Can you give me some hints?
PS: there is nothing wrong with the stuff inside the cannister and
the tubes are in good condition. So I really don't know why
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Although you said there is nothing wrong about the stuff inside the cannister, but have you really try to change part of them, some very old filter meterial will slow down the water flow ...
or you just need to take out the filter meterial temporary to check ..