I just found this thread but I'm glad to see you did the right thing and just bought the big fish without knowing for sure what they were. They're a steal at those prices and you can always find friends for them later or resell them without losing money.
I also agree with those who said to just overstock the tank. For reference, I just moved all my south americans into a 125 (put the 300 wide on hold) and so far it still seems kind of empty with this stock:
12 Orangeheads
5 leucosticta
1 red lip
2 pictus cats
1 ghost knife
1 8" Uaru
1 12" black aro
Some pics here: http://www.monsterfishkeepers.com/forums/showthread.php?t=256961
I have 6 orange Uaru babies growing out in another tank and plan to get a pair of Severums (not sure which yet). It'll take forever before those babies are big though.
Now, only 3 of my orangeheads are adults. And that has a lot to do with it. The others are all juveniles, about a year old now with the largest male being the size of my adult female. But they all school together and enjoy their space and I feel like I could add a few severums and Uaru and still have another 6-12 months before needing to thin the herd.
Of course, as you get into larger cichlids like Abalios/Altifrons that grow to 10" instead of 6", you'll want fewer. But there's always a market for these fish, orangeheads especially, for when you think it' starting to get too crowded in there.
Now that you've got the Abalios and Satanoperca though, I would consider keeping it to just those two species of eartheater. I was thinking of adding another kind (maybe some young altifrons) to my tank but I think having another kind would be weird. 2 schools (plus my lone red lip) is enough. Keep an eye on the heckelii, add abalios as you find them, load the tank up with 40+ fish, and then thin them out later as necessary.
Oh, and overfilter the hell out of it. Of course.
I also agree with those who said to just overstock the tank. For reference, I just moved all my south americans into a 125 (put the 300 wide on hold) and so far it still seems kind of empty with this stock:
12 Orangeheads
5 leucosticta
1 red lip
2 pictus cats
1 ghost knife
1 8" Uaru
1 12" black aro
Some pics here: http://www.monsterfishkeepers.com/forums/showthread.php?t=256961
I have 6 orange Uaru babies growing out in another tank and plan to get a pair of Severums (not sure which yet). It'll take forever before those babies are big though.
Now, only 3 of my orangeheads are adults. And that has a lot to do with it. The others are all juveniles, about a year old now with the largest male being the size of my adult female. But they all school together and enjoy their space and I feel like I could add a few severums and Uaru and still have another 6-12 months before needing to thin the herd.
Of course, as you get into larger cichlids like Abalios/Altifrons that grow to 10" instead of 6", you'll want fewer. But there's always a market for these fish, orangeheads especially, for when you think it' starting to get too crowded in there.
Now that you've got the Abalios and Satanoperca though, I would consider keeping it to just those two species of eartheater. I was thinking of adding another kind (maybe some young altifrons) to my tank but I think having another kind would be weird. 2 schools (plus my lone red lip) is enough. Keep an eye on the heckelii, add abalios as you find them, load the tank up with 40+ fish, and then thin them out later as necessary.
Oh, and overfilter the hell out of it. Of course.
I did not feed the tank for one night and the Uaru destroyed every sword I have. The large sword had two 26"+ shoots coming off it too. I want to Chuck Norris style roundhouse kick that fish right now. The 135 will get set up within about a month but not soon enought to move any plants.