Possible Mistake with 110G Cichlid Tank

[duanes]

The inch per gal rule is total bull, I've always felt cichlids need at least 10 gallons per inch of adult fish.
This does not mean 1 ten inch fish in 100 gal tank, more like 2 or 3 ten inch fish in 100 gallons.
This may sound harsh...
But it does mean (at least to me), unless you have 1 fish, nothing over 10inch fish in a 100 gal.
In fact I believe the gallonage should should double when a fish gets over 10 inches.
An example, putting a 14" oscar in a 110 gal is kind of like making you live in your bathroom 12/7, and only flushing the toilet as often as you do a water change.

 

[Quo Vadis]

I'd say since everyone is getting along now just leave it as it is and let them grow. Then if/when it's getting crowded you can keep whichever fish you like most. I would not get rid of the Oscar or I think you'll regret it. The GT may get too aggressive, but then it may not. I'd take a wait and see approach, though I would just go ahead and get rid of the giant danios since they will not work long run either way (Oscar will eat them).

 

[Sonofthunder]

I would get rid of the Oscar, personally, then let the rest grow up together. Would make a very interesting tank!

You are calculating the inch per gallon rule using length alone...it's actually meant to be cubic inches (length x height x width). Length alone works for tetras and other small fish since they are so narrow, but for large fish you definitely need to figure cubic inches.

 

[ShadowP]

Firstly, I see is your allotment of only 18" for your 6 Giant Danios. That should be corrected to 36 inches as they do often reach a full 6 inches length. The Oscar also has the potential to reach 14 to 18 inches overall length. Better to plan on 15" rather than 12... 74 + 3 +18 = 95 total. Now of course, if you do not provide adequate enough carbon dioxide/oxygen exchange via surface agitation and other means, you will stunt the growth of all of them. In that regard, your tank is not overstocked for the most part, however, due to the agressive nature of the majority of the species selected and their need for each their own "personal space"... yes, the tank is overstocked, and as they each mature, the most likely outcome is that tension will increase to the detriment of all.
Even neons and ember tetras become aggressive toward each other when not given enough personl space, and you aren't playing with neons and embers.

I threw the 1"/gal rule out the window a long LONG time ago. I monitor the breathing rate of the operculum of the fish at rest (not sleeping, but not having recently had major activity). On a good sized cichlid, say 8"+ of about oscar body style, about 3 shallow to moderate pumps of the gill every 5 seconds. Once you get used to this method, you can quickly tell if the fish are getting enough oxygen or not. Obviously, any fast dither fish or similar are a pain to do this way, but they have the same disolved oxygen levels available to them as the "control" group.