Hello Matthew. Here are some comments.
Tiger Barbs and Red Tailed Sharks are usually compatible tank mates. If you have one or two Tiger Barbs, they will usually cause problems. Tiger Barbs are a schooling fish, and
if you keep a group of six or more, they usually don't cause problems. Click
here for more information about Tiger Barbs.
Apparently you know that two Red Tailed Sharks will usually quarrel, and the stronger one will make the weaker one miserable.
Your Sharks must be very equal, so one does not yet dominate the other. But this situation will probably change, and so you should watch them carefully to be sure one does not
get stronger and make the other miserable. Click
here for more information about Red Tail Sharks.
There are two plants that usually do very well in aquariums. The Java Ferns and the Aponogeton.
We usually sell both of
here now to see the
live plant species that
we currently have in
stock. We almost
always have the Java Ferns in stock, and we usually have the Aponogetons. I recommend a group of
several plants of each type.
I think a Crab would do just fine and be lots of fun to watch and enjoy. It will also help stir your thick layer of gravel. By the way you should consider removing some gravel.
Your fish will do much better with a layer of gravel that is no more than 1/4" thick.
A layer of gravel that is 1" thick will almost always cause problems with your fish's health. Click
for more information about gravel.
here for comments
about how to keep live
aquatic plants in pots
in your aquarium, so you
don't need a thick layer
of gravel on the bottom
of your aquarium.