Another filter question

Joybird · Nov 5, 2016

I bought a 30 gal setup from someone and when I moved it I set it up as he had it. It's been up and running fine a couple months now and I'd like to remove one odd looking bit he had, but I'm not sure it's necessary. For anyone that's run freshwater before, do you remember those cheap old plastic grates you could put under your gravel with a tube running from it up to your filter intake to help filter your substrate? He's got it set up with that--grates under the substrate, a clear hard plastic tube running up and then a power head shoved into that opening so it's sucking water from that tube and pumping out to the tank. (I'm not sure this makes sense?)
I'd love to yank that nasty tube out of there--it's stained horribly inside and there's no cleaning it. I can't imagine it's actually doing anything for filtration? Has anyone ever seen a setup like this?

Joybird · Nov 5, 2016

Here's a photo of this nonsense.

sinekal · Nov 5, 2016

It's an undergravel filter. If the powerhead is directed into it then it's pushing water up through your sand. That would possibly keep detritus out of the sand and possibly make the sand a more effective biological filter.

What else do you have that filters the water currently? Consider if your remaining methods can handle your bio load.

if you do remove it I personally would also remove the filter under the sand out of concern it would become a detritus trap

Joybird · Nov 5, 2016

sinekal said:
It's an undergravel filter. If the powerhead is directed into it then it's pushing water up through your sand. That would possibly keep detritus out of the sand and possibly make the sand a more effective biological filter.

What else do you have that filters the water currently? Consider if your remaining methods can handle your bio load.

if you do remove it I personally would also remove the filter under the sand out of concern it would become a detritus trap

I also have a HOB filter on the tank, though i dont know the brand.

The power head intake is in the tube, directing water out into the main tank. It just seems like it couldn't be moving much from under the substrate like that? I don't think I should stir up all the sand and coral at the bottom to remove those grates though, so maybe I'll just leave it alone until we upgrade to a larger tank this winter. I just hate how it looks and there's no cleaning it. I guess I thought that saltwater tanks just didn't use those under gravel things.

sinekal · Nov 5, 2016

I don't believe they are common because they are not very effective and are hard to clean so they can become detritus traps either way. If you are upgrading soon I wouldn't think what you do will matter much either way.