Picked Up Tank #3 Used, Need Help

[VTDrew]

Hey All,
 
Picked up tank #3 used.  72 or 78 Gallon Bow.  (seller says 78, sticker on stand stays 72).  Great deal I think.  Tank, stand, hood, light, canister, heater, gravel and 9 fish for $150!!!!!!!  They guy was super concerned about the future of his fish (I actually out bid someone by $50 in agreement to take the fish). Which is why the rest of this post will be surprising, the mistakes are not my doing, so don't criticize please.
 
Fish, many of them I think I identified, he did not know what half of them were:
1 Venustus? (He claims S.A. Cichlid)
1 "Albino Spotted Spiney Cat Fish" - Still unknown ID
3 Silver Dollars (Confirmed)
2 Giant Danios (90% Confirmed, coloration doesn't seem 100% though)
2 Leporinus F. (Confirmed)
1 Tri Color Shark (Confirmed)
I am not familiar with any of these species.
 
This is a mature community, most fish are full or almost full grown.  I would say 3 years that he claims peaceful but I seen tons of nipped fins on everyone but the cat.
 
Since purchase and move, I have replaced the filter as it was questionable in operation with a hagan 110 power filter.  Replaced the aging heater with a fluval 300 and replaced the T12 bulbs in the fixture (he had one bulb operating)....another $150 but I still think I'm doing good here.  I also scrubbed the algae and salt encrusted tank.
 
I still need to do a solid gravel clean.  I was hesitant to not rinse the gravel (as it was gross) but because his water chemistry was poor at best and the mature filter wouldn't run, i wanted to save as much bacteria as I could.  I also need to reinforce the stand, its a little shakey at the joints, it can wait for summer when I re-paint it.
 
So we arrive at the questions....
1) What fish need to go back to LFS, what fish need to have their schools increased. (and why).
2) What live plants will survive this odd collection.
 

 

[Wills]

Hi Ive been in this situation before seems reasonably straight forward though
 
 
 
1 Venustus? (He claims S.A. Cichlid)  - actually South African - not really community friendly
 
1 "Albino Spotted Spiney Cat Fish" - Still unknown ID - can you post a picture? Could it be some kind of Synodontis?

3 Silver Dollars (Confirmed) -are you 100% on these? Just to rule out the risk of them being pacus?
 
2 Giant Danios (90% Confirmed, coloration doesn't seem 100% though) - Can you post a picture? There are a few similar species

2 Leporinus F. (Confirmed) - are you 100% on these? There are a few similar species?

1 Tri Color Shark (Confirmed) - when you say Tri Colour do you mean they are a type of Pangasious?

 
 
It could be the case that this could be a nice tank without the Venustus and possibly the tri colour - need to know what the leporinus are as well really but see how it goes.
 
Wills

 

[DrRob]

First up, well done on the bargain tank.
 
Pictures of the catfish and venestus would help us. However if the species is correct then the South American bit isn't.
 
Ideally, lose the tricolour shark. they need to be in groups, ideally 6 + and they get to over a foot long. You're looking at a huge tank to do them justice.
 
In the mix you have, the Leporinus and the giant danios will appreciate a good flow, the silver dollars will not, and will appreciate lots of cover and plants, as well as a larger group.
 
My first question really, apart from can we get pictures, are what water do you have and what direction do you want to go in.