Originally Posted by Eel lover50
Hi, I have noticed that my Cory catfish scours the bottom of my tank for leftovers. I recently realized I need a gravel vacuum. Will the Cory have to rely on the shrimp pellets by themselves or will he still be able to bottom feed? Btw, how do you use a gravel vacuum?
Corys are bottom feeders and prefer a tank bottom with a reasonable amount of debris on top. They sift through the small pieces of gravel, plant material and small pieces of driftwood for food, so you don't need to vacuum the substrate. Another reason for not vacuuming is everything eventually dissolves in the tank water and that nourishes your plants. A third reason if you want one, is disturbing the gravel causes small particles to mix around in the tank and that clouds the water.
You can use the vacuum to simply remove a good amount of the tank water every week or so and of course replace it. This is all that's needed to maintain healthy conditions for your fish and plants.
Just an opinion, though.