Reversed Gravel Filtration

[Lion8974]

I read a DIY article a few years ago about a reversed gravel filter system. For those who don't know, you have tubing go under your decorative rocks and gravel. Instead of sucking water and debris into the under gravel filter, your pumps blow water underneath your gravel, keeping dirt and waste from resting on the bottom of the tank. It blows it up and is taken in by the over flow for your filtration system.

The new 300 gallon temporary tank I have my cats in (RTC and a TSN), I am currently pushing two 500 gallon pond master pumps into 1/2" pvc tubing underneath my gravel. With the cats being messy eaters sometimes, this is a blessing to have. I want to ask peoples opinion on these two questions:

1) The 500 gallon pumps push just enough to push debris up like a plastic bag in a mild breeze. I was thinking of swapping the 500's out for 850's, but I want to know if you think the streams of water being pumped would cause irritation to cats with the random outlets?

2) How would I go about adding aeration bubbles to the PVC lines without effecting the pump flow? Any recommendations? I was thinking of just taping a small hose and nipple attachment and just plug in an air pump, but that doesn't work. Water pressure spits the nipple and tube out.

All input is welcome. Even theories!

 

[WyldFya]

To get the air to be injected, you'd need to silicone the airline tubing in. As far as upping the flow, that would do a better job (based on your description), but as far as irritating the cats... it may or may not. Depends on the gravel type, and your cats.

 

[fishdance]

Depending on where your pumps are, you can make or add a venturi to suck in air. I doubt you will be able to introduce air with an airpump and airline since water will just take the path of least resistance and water will escape out using your airline. Why do you want to add air to your waterflow anyway? You could add it by airpump BEFORE your pump intake but this may make your impellar noisy.

Increasing flow will not bother the catfish. They will easily find a back eddy behind rocks etc if they need to. They are river species remember and the TSN is often found in white water.