It looks like it may be a while before I can get my sump built. I'm wondering if a sponge filter would work in the 55gal for a couple of months if I kept the tank lightly stocked with maybe 10-15 small fish, Kuhli's, bristlenose cats and maybe a few Endlers. I could hold off on the endlers for a while if that would overwhelm a sponge filter.
I just don't want to buy a HOB that will end up being out of use as soon as I get the sump built, and a sponge filter is easy to make and the parts are re-usable and cheap!
I don't want to buy a new 20 long @ $30 to turn into a sump and the people around here havn't gotten into yard sale mode yet.

Sponge filters are excellent at bio filtration, but not so great for mechanical filtration. I have them running in all but a few tanks, and all the tanks running them are overstocked breeding tanks. Breeders use them because they work so well at bio filtration, mechanical filtration is taken care of through water changes.

Here's an overstocked 55 with a couple of homemade sponge filters for bio filtration, a couple of homemade powerhead filters for mechanical;





A sponge is the only filter in this tank, a 10 gallon with 263 angels;




I wouldn't hesitate to stock up a 55 that has only sponges for filtration.

OMFG That's a LOT of angels for a tank that size!

Thanks for the imput, now I gotta get Hubby to take me to the home store or have my mom buy me the sponge on her next trip. I guess I better go re-visit those DIY links.
:woo: One step closer to 'up and running' !

It's just pvc pipe with a cap, and a piece of pond sponge filter.




Just drill some holes in the pvc, stab a hole in the center of the sponge with a good size knife & slide it on. I put a little gravel in the bottom by the cap to weigh it down, sponge floats real well.

The sponges cost $6, pvc is cheap, for around $10 you have bio filtration for a 55.

Those angels are in a 29 now, due to be split up into a second 29 in a week. They should be ready to sell a couple of weeks after that.

Cool, Thanks!

Everyone I have asked about open cell sponge asks me if sea sponge will work, will it?

Ok, I ended up with 2in foam rubber, I figure to cut a piece twice as tall as I need and fold it in half and wrap it around the PVC. I'll post pics when it's done.

I made 2 of them, 1 is 1 ft PVC pipe 1inch diamater, I figure on putting rocks around and possibly on it to hold it down.
The other one is a 3 inch pill bottle with 2 in of sponge for my 1gal hex betta tank(no betta) that I'm starting my plant bulbs in, I have one question..................

HOW the :cuss: am I supposed to keep the damn thing sunk?
It is too narrow and short to put enough gravel in it to sink it, at the moment I have a rock 1/4 the size of the tank in it to hold it down but that doesn't give my plants much room.

Sea sponge is closed cell, if it's the type I'm familiar with. If it picks up water & you can squeeze it out, it's closed cell. Water runs out of open cell. This may be part of the floating problem.