35 Gallon Cichlid Tank

Firemouths can be diggers so I would go with sand. You are going to have a heck of a time keeping ANY plants with cichlids, and just remember that seeing as how a firemouth is a CA cichlid you won't be able to keep any Africans with it. Personally I would recommend you go with some of the African Riverine cichlids such as Jewels in a 35 that can be kinda small for fish that need territories or problems will ensue.

 

Well for color mbuna are the best way to go but I wouldn't suggest mbuna in a 35, they need right much space. In that size tank you could make an awesome shelldweller tank. Take a look at some of the shelldweller species from Lake Tanganyika.

 

I would worry about the ottos getting eaten and cichlids love to eat the eyes of many plecs. I am not for sure about the species you listed I will do some researching and find out for you tonight after work though.

 

The cichlids pretty much enjoy digging in the substrate for food themselves... so maybe you could try for a while with them only? If it gets too dirty, you could try looking up some African catfish to stick to the theme! ;D

 

Choose whatever you want! But if you want gravel, make sure it's round and smooth so your fish won't hurt their lips

 

This is a dwarf Mbuna, and as such, can be housed in tanks not usually recommended for Mbuna species. A 36-inch tank will suffice, but as with all Mbuna, bigger is always better. In the wild, these fish are found together in extremely large groups swimming in and amongst rocky habitats. Surprisingly, members of these groups show very little aggression towards one another.
a minimum of twelve should be kept in any size tank to help disperse aggression. This not only keeps a single male from being dominant over all others, it helps females and sub-dominant males from being chased to exhaustion (and death) by getting "lost in the crowd". A small group of 5 or 6 simply will not work, as the dominant male will systematically kill off each tank mate until only he remains. Male to female ratio is unimportant when they're kept in groups of this size, which is a bonus, because accurately determining their gender can be a futile task. It's very important not to house these fish with similarly colored species (e.g., Cynotilapia afra or Metrialclima lombardoi).

ottos...i agree with HBIC and not do them with african cichlids. i have a common pleco in my 55g mixed african, when smaller he did get picked on some and now that he's approx 8in he holds his own. with a tank of your size you may want to check into the synodontis species of african catfish.

2 of each of these in a 35g, imo, would be a disaster in the making, too much aggression.

 

Crushed coral is 100% fine for cichlids. I always used it with mine to help buffer the water and keep the ph up.

 

Yeah, cichlids need rather alkaline and hard water as far as I know *nod*
But... is crushed corals sharp? On pictures I've seen it somehow looks kinda' smooth?

 

I think I'd go with the Neolamprologus similis.

 

That's a pretty big difference there. The Neolamprologus similis should be at around 8.0 and the Butterfly Fish around 6.5. If you do pH of about 7.5ish that should be fine though. Just make sure to drip acclimate them slowly depending on what pH they come from.