I have a filstar on my planted 55g. For some reason lately it has a lot of bubbles. The canister will not fill past the top of the top basket which is obviously the reason for the sputtering and bubbles. I can loosen the lid and the water will fill but then drop right back down to the height of the top basket.
In the bottom basket I have the two pads it came with and a puregen pad. Second has a pouch of matrix and top has stock floss pad and very small amount of pillow floss.
I've cleaned tubes and don't notice any leaks. Why would it be acting this way?