I'm new to the forums, set up my first tank (at least since I was a kid) about five months ago. It's a 29g tall that seems to be going well - currently has 3 hi-fin variatus (platys; 2 f 1 m), 4 white cloud minnows, 6 neon tetras, 5 otocinclus, and 2 honey sunset gourami (sex uncertain; they're young and the fs attendant wasn't sure). The gouramis are a new addition, otherwise the tank has been stabe for a few months. I'm setting up a 2nd tank (20g long) and I want to branch out a little. Tank size is obviously a restriction but I've got another problem. I live in Arizona, so the water coming from the tap is hard and alkaline. 7.8 pH range. I get my fish tank water from the tap outside, so it bypasses the water softener (which just changes the salts; it's not a RO system), but that only helps so much.
I've been looking at gouramis, dwarf cichlids, and loaches (not all necessarily in the same tank; I'm going to move some of the fish from the 29g to the new one, so some could go into that one)... but none that are of a suitable size for my tank seem to like hard, high pH water. I'm watching the honeys to see how they handle it, I've only had them for a few days.
I have a number of the "silk" type fake aquarium plants; I'm willing to look into live plants but I'm not currently keeping any. The new substrate will be sand; the existing is rounded gravel.
Any suggestions? I know the platys are OK with higher pH but they're honestly my least favorite fish of the existing collection.