Most plecos get huge. Maybe the golden nugget stays small. I think there are a few that stay less than 6 inches. Common plecos get well over a foot long and so do most catfish.
There's also a few catfish that stay small too. I had one that when it got bigger ate all the other fish. It got a bacterial infection and died.
I'd think that the sharper edges are slightly better for plant roots than rounded, but if you have fish like burrowing eels, fresh water flounder(halabit), and dojo loaches they prefer the rounded gravel because it doesn't cut them like the crushed stuff.
I've grown plants in the rounded med to small particle sized gravel with no problems.
They don't really -clean- it so much as they do stir up all the sh*t laying on the bottom so it can be more easily sucked up by the filter. There isn't much out there that will do that better than a small shoal of 6, or more corys. They've helped me a ton in my 30gal as there isn't much room to gravel vac (its 26" tall) and I can't pull up all my plants just to get to the built-up areas of sh*t.
I originally had 3 Striped Raphael cats for this purpose, before I learned they grew to 6" unlike petsmart's quote of 4". They didn't do nearly enough stirring up tbh, anyway. Even by night as they're noctournal.
Malaysian trumpet snails are good at doing what I mentioned a couple threads down...stirring the substrate so you don't develop sulfur pockets like the problem I'm having. They'll also hopefully keep your sand from getting compacted so oxygen and other necessities can get to your plant roots.
Just image google em. My first batch hitchiked on a piece of driftwood I bought with java moss attatched. I had hundreds in my 16gal for awhile, I think the population has leveled off as I fed less and less.
I actually stirred some more bubbles out today. Smells freaking awful when they pop at the surface. I still have yet to lose any fish thank goodness..
I have had Cory for a while and I like them a lot. They are one reason I have sand...their barbels are sensitive to substrate and shouldn't be kept with something sharp like crushed coral. Large size substrate is bad too because their food falls between the large pieces and they can't reach it very well. The Cory are good at eating left over food and some algae. They are darned cute too, and lots of fun to watch. Remember that they are air-breathers and need to surface for air.
There are some living creatures that process fish poop. I've read that some shrimp do and I think snails filter it out through the way they naturally eat. I was just looking into Amano Shrimp and I read that they will eat fish poop. I think what people hear sometimes is that no fish/invert processes fish poop so efficiently that it could replace using a filter or weekly water changes.
Ya I have looked at pictures of them, they are preety cool, I just want a brown/tan coloured sand, but I havent even seen corydoras at th store yet, so I will have to wait... and I still have to get my new light, and then sand...
I like the sand and gravel that aquarium stores sell that's covered with polyurithane or something. I origonally thought it was too processed as I'm into the more natural stuff, but It looks really natural with actual rounded and sifted peices, so it's a nice consistancy.
