New to Forum - starting a 75 Gallon Clown Loach Tank

[Diana]

You do not need to drill large holes in the sponge. I cut an X through it from one end, and not cut all the way through, but do not remove any sponge.
If you find a thin, flat sheet of sponge material (pond department, again) this can be rolled into a tube, and held with zip ties so it is snug enough not to slip off the pipe until you want it off for cleaning. Not too tight, or it will be very hard to put it back on.

PVC parts do not need to be glued when they are used inside a tank.

The glue is not toxic once it is dry. It is not really glue, but solvent. It dissolves the PVC pipe and fittings, and as it evaporates the parts in contact unite.
I would run water through a new manifold via a hose pipe for a few minutes until you can no longer smell the solvent.
I have used PVC for external plumbing (glued, for this use) and never had any problems. After the parts are glued I would lay the assembly out under a tree and deep soak the tree while running some water through the pipes.

PVC can be painted, too. There is a spray paint available here for outdoor use, patio furniture and such. It is called Krylon Fusion. Designed to work on plastic, and is aquarium safe once it is dry. For use as a manifold like this where almost everything is buried it may not need painting, but for other uses it hides better if it is painted.

Soil Master Select seems not to be available any more. It has been replaced with Turface. They are used in sports fields, and are available at Lesco. (USA, maybe Canada?) I have both SMS and Turface in several tanks. They tend to remove the KH from the water, and can drop the pH quite low. It stabilizes after a while.

[krazykat]

Hi Diana! Thanks for the tip on the paint - it's like you were reading my mind ! As I was dry-fitting my manifold, it seemed like the parts would stay together without glue and so was heavily considering not using the PVC glue at all. We'll see.... I was thinking of using rubber bands to hold a rolled up pad filter onto the intake but your zip tie idea sounds a lot better to me! Tried to take pictures of my setup tonight but my camera needs to charge up longer. The batteries have been completely drained .

[krazykat]

Hey krazykat where are you? I'm in Bellingham. I also used the foam filters from home depot, though I've seen other options at my LFS and I think PETSMART. I didn't glue my pipes together and I haven't had any problems yet. One thing I have noticed is that after it's all installed and working, and you want to take the foam off to clean it, it's real easy to pull the manifold up through the sand, and very difficult to get it back down! So weigh it down good with some rocks and be careful when pulling on the foams or powerhead.

LOL! Can you imagine trying to get the manifold buried right back in the substrate once you accidentally pull it up? It would be a PITA! Thanks for the heads up, plaalye! I actually saw a pond pump prefilter at Lowe's and purchased two of these. They seemed perfect - there was a foam case with slits to allow the water but not loaches in, and they fit perfectly onto a 3/4" PVC pipe so that I wouldn't have had to drill holes into the intake pipes, BUT there was a very strong odor - most likely VOCs, which I did not think would be very good for such a small, closed system, so I took them back. Will probably start off the manifold with rolled up filter pads that I got from Petsmart - those blue bonded ones - until I find a better option. Please feel free to make recommendations, anyone.