One or Two ?

[GreyMan]

Hi, need some advise. I have a 30 gallon tank with an overhead filter. I have recently added a layer of bio rings in the filter box. That take up some space. Before this, I have no bio rings but 2 pieces of filter woool. Now with the bio rings, I can have one layer of the filter wool, 2 if I squeeze them in but with some difficulties. So is it ok juz to have one piece of filter wool ? I am afraid that a single piece is not sufficient to provide mechanical filteration and will cause the bio rings to be clogged up. Thanks.

[bullosa]

The filter wool normally settles down a bit after a week or two...you should be able to put in 2 of them. But dont sacrifice the bio rings cause I think they are the crucial for your filteration system. All the best.