Penguin 375 flowing out of middle section

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Aquarium Advice Newbie
May 20, 2023
Like the title says I have a fairly new setup(roughly 4mo old) and the Penguin 375 has been working great until recently. I noticed flow had slowed down so I popped in new filters thinking maybe the old ones were due for changing. Still didn't resolve it, so I removed it and cleaned everything.

The impeller seemed ok and spun freely and there wasn't any build up blocking it to reduce flow. Put it back together and slapped it back on the back with new filters and flow was great. But only one biowheel spun. I figured well maybe the one has too much build up on it, but it doesn't look like it. It doesn't look damaged and the "bearings" that it sits on is clean and it'll spin when I spin it. But flow was good so I let it go.

Now a week later flow is lower than before, and most of the water is coming out of the middle section.....There's nothing blocking the filters, and the filters are clean....

What would cause this??? I'm debating on buying a new one since they're only $60 at my local petco/petsmart right now and replacing it. But I'm afraid it'll happen again. This is in an established 75gal tank and I'm afraid if I try to switch to a canister setup it may throw off the tank. That and they are expensive.

Any ideas?
You don't want to totally replace your filter media because the majority of the nitrifying microbes are going to be in that filter media. You can rinse them off to get rid of the "gunk" that accumulates on them but that's as far as you should go.

As for the flow issue, make sure the filter box is level and that the bottom of it is angled correctly from the tank. You may need to add a sponge of piece of styro or cardboard between the tank and filter box to get the correct angle if there is no part from the filter to do this.

Make sure that there is no obstructions causing the wheel not to spin. Use a Q-tip or toothpick to make sure the wheel holders are clean. ( Your eyes may not be able to see what your Q-tip can. ;) )

For the reduction of flow after only a week, it sounds like there is a lot of material going into the filter which would mean you may be over feeding or dead plant life that should be removed before it decomposes in the tank.
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