Canister filter not pumping


Hey there I'm needing some advice on my filter. I don't know exactly what filter it is, its a Marineland canister but it doesn't say the model. It's large for a 75 gallon tank. It was working just fine until I took it apart to clean the filter pads. Now it won't pump water through.

ok some more import info - I found fish fry in the bottom of the filter, I carefully removed them and placed them in the grow out tank. I don't have a find prefilter so I put a sock on the intake tube. Could the sock be causing the filter to not pump? I'll go buy a proper prefilter, but what else can be the cause? When I prime the filter it moves water through, I plug it in and it peeters out. The motor is running, it sounds normal.



Did you rinse the sock? Overtime it may have collected debris and now it’s reducing the amount of water the filter takes in


Have you tried taking off the sock and seeing if it goes back to normal? If it doesn't, then it's got to be something in the filter. I know you said the motor's normal, but double check and make sure all the parts are locked in properly. Mine use some sort of magnet system and if the magnets aren't clicked into place, that problem happens (Disclaimer: mine's a different brand, so my tips might be irrelevant). Check if there's blockages in the tube too, perhaps rogue filter floss. Otherwise, I'm lost - hopefully someone with your canister filter can give better advice. And congrats on the fry!


The only thing moving in a canister filter is the impeller. Have you checked it ?

When this happens to me I just plug the head of the filter without the canister to see if the impeller is working. If not, I try to fix it until it does. If it works, then your problems might be your sock or other debris blocking the flow.


Try the ATI Filter-Max III if you want a decent pre-filter.


Let me understand - you open the filter to take the fry out - then put it back together and now water doesn't flow when you plug it in.
Does this filter auto-prime or did you prime it or otherwise let it fill up. Also if it has on/off valves did you re-open the valves ?

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