He said a 10G... I don't think that would make a nice rift tank.
tank is one that has saltwater. So you can't do a FW
tank that is like SW
There are many styles of SW
: Fish only, fishless, reef, etc. But it seems that inverts are often an important part of any SW
tank, where as they are just another addition in most FW
. Of course, many of the SW
inverts are not going to be visible with the naked eye.
The only FW
inverts I see regularly at my LFS
are shrimp and fiddler crabs. I don't know if the crabs will eat the shrimp, though.
Anyone will tell you the problems stocking a small tank. But you still have options. In fact, you could even go with a low-water setup for hermit crabs. (Get a secure top, though... they are climbers.) Maybe you can even squeeze a pond/land environment in there with the right critters.
There are many reasons people go for the expense and hassle of SW
... and most of those reasons cannot be reproduced in FW
. So I would suggest stop thinking "like SW
" and take a look at what FW
offers that SW