Stocking for a 75 gallon

Ok thanks unseenone, the knife I was talking about is the black ghost knife that is commonly carried at LFS, and due to my addiction in 7-8 years I will very likely have a very large fish tank lol. While an option I have done research on them in the past and they arnt much of a centerpiece fish because they hide so much which I know, but I have always been interested and kinda wanted one
 
They are docile for a cichlid I think it will work I have always kept tetras with my larger cichlids it helps with agression In my experience when the lights go off black knifes will pick on the smaller fish in the tank.
 
Yes if I went the black knife route the fish in the tank would have to be larger than I have now. Are there any other fish like the keyholes in temperament that you can think of as well?
 
You know what else I like are "bumblebee catfish" but the store says they get to be 10", online its saying NA species gets 2.5" and the asian species get 6"... any idea whats what with these guys?
 
Would a Altolamprologus Calvus be acceptable with a tropical community? It is a cichlid but it stays fairly small I read (5 or 6 inches as well) and is supposed to "mind its own business" anyone have any experience with these and fish as small as a full grown platy?
 
Calvus are Tanganyikans and if you wanted to do them you might be able to do a decent species tank with the 'typical' African setup (hard water, high ph, rocks, that sorta stuff) but if you want them for a tropical community (Tanganyikan community would work), its a big no.
 
For the lower levels, you will have fun with loaches. I have Blue Botias (http://www.loaches.com/species-index/yasuhikotakia-modesta), but you could get Clown Loaches too. Give them tubes (either pretty natural ones or cut up some 2" PVC pipe) and watch them play! Oddly, I have one that grew big (6" without tail), a couple that are medium, and two that are staying small, after 4 years.
 
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