Wow some of those fish need some are going to get really big. Like the tin foil barbs and the pleco (if its a common or a gibbi, can you get any pics?). I would take these out (if the plec is a common) because both of them need around a 6ft tank. And then add 3 or 4 more silver dollars maybe an other while line pim and then a smaller species of plec if you want one. As for cichlids I think the main concern is the festivum, the other pims and the dollars are quite tough but festivums can be a bit squishy but some are quite tough. How about an ellioti? or a Blue Acara? depends on what you like I guess. If you dont mind making it non biotope to SA you could try Kribs or if you can find them one of the rarer Pelvachromis species?
I really dont think the pleco is a common one because he has stayed the size he is at for years. His coloration looks like a common one though but he is only five inches max. There has always been tinfoils in this tank.
Your right about the festivum i had three and two diel only the largest one is left he usually hangs out with the silver dollar. I think the festivums killed each other though the other fish never bother them.
Could a blue Acara or a severum go in this tank without hurting the festivum? He is kind of a puss but no more of a puss than the sivler dollar and he is almost as big as the dollar which is probably 7-8 inches
Hmmm can you post a pic of your plec there are a few L numbers that look similar to commons but stay small, we might be able to get a positive ID for you just so you know what you are dealing with. How old are your fish at the moment?
With the Blue Acara and Sev, I would go for the Blue Acara I think it would be quite a nice combo, an ellioti would look good against them as well I would avoid the Sev while a 55g tank is the minimum for them they really do get big and are very active so I would think 75g is a minimum for a sev, I am stocking a 55g at the moment as well and I really really want a sev but I know in the long run its not going to be fair on the fish and I dont want to end up damaging it through a small environment.
The silver dollar is the oldest probably around 12 years old, the pims are probably 4-5 years, the pleco is at least 2, and the tinfoils are the newcomers less than a year old and idk about the festivum i got them when they were adults.
Yeah lol at least 12 years he could be up to 14 years old. He is a BIG boy and very slow and calm. I had some old tinfoils in that tank one of them made it to 15 years
ill take some pics when i take some of the plec :]