Okay, it's been decided. Ordering a second 45-F since my current one is being used for coral frags.
Also going with Amazonia for substrate. With my tap water and the buffering, parameters should be perfect for Tigers and Neos.
Gonna place the order today.
Now just have to settle on a light fixture. The 45cm fixtures at AFA are sold out, so I may go with one of the others on eBay. Tank wil be low light, so it won't need anything fancy. Just has to look nice - like the Archaea telescoping 45cm fixture - because I can't really suspend anything over the tank. Prefer the top of the tank to be primarily free of obstruction so I can jab my hands and tweezers and such in there without having to move a fixture around.