Just a standard 29g aqueon. 30 x 12.5 x 18.75
I would be using water from my RODI to have clean source water. So should be 0tds and pretty close to neutral ph. Due to rodi I'd assume 0 CH and KH.
I mentioned planted tank. I do have a spare reef capable light that will work for a planted tank. One other thought I had was maybe a discus pair.
I would recommend soft water fish here. Plants will obviously need some mineral nutrients, but these can easily be supplied with liquid and substrate fertilizers. I have zero GH/KH water out of my tap and this works fine for soft water fish, with a very few exceptions.
Light is the key with plants, and different plant species have differing requirements when it comes to intensity. Fish are affected by the overhead lighting, so that needs to be borne in mind too. Discus for example, since you mention them, should have less light rather than too bright, so plants that will manage with low to moderate light will be best. Or you could go with a more authentic habitat, no lower plants, lots and lots of wood and branches with sand substrate, and keep the plants limited to floaters. And there are many variations in between. Knowing the light data is next.
Discus are shoaling fish and should be in a group, which requires at minimum a 4-foot tank. Some might suggest a bonded breeding pair in a 30g but I would want more space.
I have two of the Aqueon 29g tanks among those in my fish room; it is quite a nice size, but stay with smallish fish. Just for ideas, I'll add a few photos of just the 29's over the last few years; they get changed now and then. The third, a SE Asian aquascape, didn't hold together very long, as the light was insufficient for the Wisteria. I now have Amazon swords which just manage under the thick floating canopy, which is there for the Chocolate Gourami.
Byron.
