I have recently upgraded my fishtank. The new one has 3 under-gravel filters and I am using my old charcoal and wool filter as well. I am using a Sonic 9905 pump that has 2 air connections. When I first set it up 2 days ago, all three gravel tubes, connected by T pieces, flowed with no problems and the other filter had it's own tube.Now, either the 2 tubes closest to the pump work, or the further one. They seem to change randomly.How can I get all three to flow constantly?
If the T piece do not have a regulator on it, replace it with one that has. This is usually called an air regulator. It has a knob on it that you can use to regulate the flow of the air in the tube. Or you can buy a piece of valve that can pinch the plastic air tube so that you can regulate the air that goes into one tube or the other. These are available in your LFS. Ask them and let them show you how they do it.
