easy peasy
can you explain how you made it in more detail? sounds like it might just work for a project im working on.
I hope this tangent from the topic is OK but I can't imagine starting a whole, new thread for this. Hopefully I can make it relevant.
I got a weak powerhead from a discarded filter barely rated for a 5gal tank. Gph I don't know but not many. Then I
got a plastic tennis ball can and put a hole in the bottom,
(note that I created no spout, spigot or other conduit, just the open top of the can, even all 'round)
jammed the outlet of the powerhead into the hole,
Jammed some poly-fil into the bottom,
Poured sintered glass rings on top,
Super-glued two suction cups to the can,
Placed the filter in the tank, suctioned to the back wall and just deep enough that the top of the can was around 1/8" or 1/4" below the surface,
and then I plugged it in!
The filter is placed just barely underwater so its outflow turns over the surface to expose more water to the air, producing a very gentle, low turbulence aeration.
I'm hoping these rings have the right structure to encourage denitrification in the conditions my filter creates. The specifics of the biomedia can greatly affect the functioning of my filter since I'm trying to maintain a pond-like stillness while at the same time supporting lots of fish 'n other critters. So very good nitrification/denitrification in a small volume (small tank) was an important goal for this little filter.
So if substrat pro works better and Odyssea bio glass is inadequate, I'd like to know ahead of time instead of having to start with the cheapest biomedia I guessed could handle it and using the stuff for a while until I could tell if it works or not and then maybe having to buy and try out a more expensive alternative.
More thorough knowledge of one's tools and materials expands one's imagination. I mean, fish keeping is more than a hobby, it is truly a very broad craft and craftspersons, even hobbyist-craftspeople, should know the properties of what they have to work with.
DIYers CREATED this "hobby." The industry should honor us with a little more data.:wall: