Hello,

I have just purchased a new 110 gallon aquarium (48*18*30). I have been placing much thought as to what and how many fish I will have in it. My plan is to have 2 oscar, 1 jack dempsey, 1 green terror, 1 red lobster, and 1 clown knife. Is this a reasonable set up? If not, what suggestions can you make as to the number or types of fish for this tank? I was thinking that I might want to skip the clown knife and place more fish in the tank. Any thoughts?

Thanks

I have a jack dempsay in with my oscars. He is a right softy and gives no grief. However they are named after a boxer from the 20's or 30's for a good reason they have a reputation for being aggressive so keep a close eye if you keep one. The same goes for green terrors, i had one that was battering an oscar twice its size. Again all fish are different so you might be one that is ok. I cant say about the other fish you had mentioned as i have never kept them

Alternative fish could be a texas, firemouth, blue acara, convict (can be aggressive), nicaraguan, Urua, silver dollars, chocolate cichlid, geophagus (various sorts), severum

I think you will be pushing your luck with the fish you have mentioned. Two Oscars is fine, but I don't think you can put the rest that the fishermen. Jack Dempsey's and green terrors can both be aggressive cichlids. However, choosing between the two, I think Jack Dempsey's would probably be the less aggressive. It's difficult to say really, some people keep these sort of fish together with Oscars and have no problem, other peoples have serious problems so it's really hit and miss. Regarding knife fish, some of these can get extremely big. Not sure about the lobster, I believe these can grow to around 5 inches. There is a possibility that a very large Oscar could attack this and kill it, and then eat it.

I would say that the most important fish for me to have would be the 2 oscar and 1 Jack Dempsey. The others are negotiable. Any other suggestions to go with these fish and my 110g tank? How about silver dollars? Are they entertaining? I have heard you do need a group of them.
I would welcome any suggestions for tank members for these 3 fish.

Thanks

Silver dollars do like to be kept in groups, however when compared to an oscar they are small. I would say 3 is the minimum but 6 would look good. With them stick to the smaller cichlids like the blue acara or firemouth. Blue acaras have some nice blue lines around the mouth and good body colour. Firemouths have good colour to them and when they front another fish up they have a flap of skin between their gills which they flare out and shows up red, i can only describe it at majestic

Thank you for all the great advice. So how is this to start up my 110g?

2 oscar
1 JD (smaller than the oscars)
1 blue acara
1 firemouth
3 silver dollars

Sound ok?

Is starting with 2 oscars too much? I have heard that its better to start with 2 than to try and add another one later.

Thanks

It is better to start with 2 oscars than to add one later. Some oscars just will not accept another. I heard someone say some they get tank proud and wont accept another. You still might find that they wont get on when they get big or that they might start breeding. If they start breeding then you are gonna have 2 oscars at one end of the tank and the others at the other end, or the oscars might beat up and even kill the others. So you may have problems when they get big.


You list is ok but you might find you have to do lots of water changes to keep the nitrates below 40 but preferable below 20. Test the nitrates at least monthly and if nitrates get too high either increase how often you change the water or get rid of some fish. I would do 50% water changes every week from the start (housepipes connected to mixer taps are a good idea)

As long as you are aware that you may have to get rid of some fish when they get full size (and you know where to rehome them) then go for it. As said before keep an eye on the JD tho

A word about feeding only feed what they will eat in 3 to 5 mins once a day once the oscars get to about 5 inches