I recently purchased and am cycling (without fish) a 55 gallon aquarium and I wanted to base a tank around a Jack Dempsey. I talked to a guy at the pet store, and what we came up with was one (MAYBE two, non-breeding) Dempseys, one Green terror, one Texas Cichlid.

Is this overly optimistic if it was just these three (or four)?

Jack Dempsey:
-Try to keep them with fish of similar temperament (other Central American Cichlids). Watch for aggressiveness and remove or use an aquarium divider if necessary.
-they will get more aggressive the more cramped they feel, especially if you have a mated pair. They will hold their own against more aggressive tank mates.
-Anywhere from 6 - 10 inches
-If given a large enough tank (55 gallon or larger) you may not see them being overly aggressive. If you cramp them into smaller tanks, like most fish, they may become more aggressive. Watch them closely.
-55 gallon minimum for one Jack Dempsey, much larger for multiples.

Green Terror
-8 in (20 cm)
-When young they may be kept in cichlid community but as they mature they live up to their name and will terrorize all but the largest fish. It is best to keep them in a species tank.

Texas Cichlid
-Males 12 inches. Females smaller.
-Aggressive, territorial, belligerent, temperamental
-When small, Texas cichlids will mix well with barbs, but, oddly enough, not with other young cichlids. Chocolates and jaguars, for instance, beat the crap out of little Texas cichlids -- even in a 55. In addition to hogging the food, the other cichlids shred their fins, peel their scales, and finish them off. Little Texans fare best when kept with their own kind. The fast growers and slow growers co-exist fairly well.


I took all this information from web pages I found by google, and I have never kept Cichlid's.....yet but my gut would go with no. That tank would be a bad idea. Jack seems like he might be okay but the other 2 don't seem like they will fare well together. Maybe introduce the Texan when he is full grown or close on it. If you could make sure the terror is the smallest in the tank then that might work too.

So, 1 Jack with 1 Terror runt of the litter to keep him in line and 1 full grown Texan might work. It falls below the 1 inch of fish etc etc rule but, in this case, you might want to discard that rule and go for something more conservative anyway. Don't think I would add a second Jack to the tank. That would bring it pretty close to the 1 inch.

Good luck!!

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10gal fry tank planted with Wisteria, Java Moss, Anuabis and Anacharis
35gal Sponge Bob tank with live bearing tropicals (daughters tank)
15gal planted with Swords, Java Fern, Wisteria and Red Rubin housing 10 fry and 2 bladder snails
55 gal with Oscar (future planted tank with angels and flowerhorns)
55 gal Community tank (platys, mollys, guppys, glass catfish, angels, phantom tetra, red eye tetra and swordtails)

It just so happens that this store will sell near adult texas cichlids and very small green terrors.

I kinda thought that the two Jacks might be wishful thinking. But what about a smaller one like a firemouth or a geophagus? This store has Surinamensis and Jurapuri.

I had 3 JD's in my 55 with 2 firemouth and a few convicts and they did well together for over a year, no aggression and they were not as cramped as it sounds. the jd's reached around six inches and they always swam together. I only tore down the tank because I moved from Pa to Fl. That was my experience and would not claim it would be good for anyone else. I did get all of them in that tank very young and raised them together, that might play a role in their success together.

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55 Gallon Planted dirt bottom,Reproducing colony of Heterandria Formosa(Least Killifish), 2 Dwarf Puffers, 5 or so Gambusia, 2 Swamp darters???, Several Wild P. Latipinna(Sailfin Mollies), a handful of Jordanella Floridae(American Flagfish), 1 Lepomis Macrochirus(Bluegill fry)

Firemouth
- Up to 6.5 inches (17.0 cm)
- They are territorial but will rarely bother other fish unless they are in the spawning ritual.
-They are peaceful for a Cichlid and should be kept with similar tankmates. In a large tank several pairs can be kept. In short they are a relatively peaceful and easily kept fish.

Geophagus Surinamensis
-10-12 inches/25-30cm
-a peaceful, relatively non-territorial cichlid
-Being more peaceful in nature than most cichlids of this size, they are more suitable for large community tanks as they will not bother smaller fish.
-this peacefulness makes them less suited to tanks containing other large, more aggressive fish. When in situations like this, they tend to spend a lot of time hiding and can become stressed very easily.
-These fish are peaceful by nature, considering their size, and are suitable for large-scale community set-ups containing smaller SA species, such as Tetras and Corydoras catfish. They do not consider smaller fish to be food, and generally will not pay them much attention. They also are very tolerant of each other, so can be kept in larger groups if tank size permits. However, they tend to do poorly when in tanks with more aggressive species such as Oscars, as they prefer to run than to stand and defend themselves.

Satanoperca Jurupari
-Up to 10" (25cm) Total Length
-One of the first things to understand about this species is that your local fish store probably has it mislabeled, or confused with the other members of the Satanoperca genus. You may have to put in a little bit of effort to properly identify the appropriate species when you have brought some of these fish home. The S. jurupari is often confused in the hobby with the S. leucosticta. The easiest and fastest way to differentiate species is the absence of white spots on the operculum of the S. jurupari. You will also often see a mislabeling of the S. auticeps, S. daemon, and if lucky the somewhat harder to find S. lilith.

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10gal fry tank planted with Wisteria, Java Moss, Anuabis and Anacharis
35gal Sponge Bob tank with live bearing tropicals (daughters tank)
15gal planted with Swords, Java Fern, Wisteria and Red Rubin housing 10 fry and 2 bladder snails
55 gal with Oscar (future planted tank with angels and flowerhorns)
55 gal Community tank (platys, mollys, guppys, glass catfish, angels, phantom tetra, red eye tetra and swordtails)

The website didn't say much about the Satanoperca Jurupari so I can't really comment about that one. I like the way the firemouth sounds but that one might be too small to keep with the Terror. So, Geophagus Surinamensis might be the best choice to go with, making sure that he will be bigger then the Terror so that this docile fish won't get picked on, since he won't defend him self if he does.

Good luck, hope I helped. Would love to see some pics when set up. Your so luck, I live in Newfoundland and we have a hard time getting nice varieties in fish.

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10gal fry tank planted with Wisteria, Java Moss, Anuabis and Anacharis
35gal Sponge Bob tank with live bearing tropicals (daughters tank)
15gal planted with Swords, Java Fern, Wisteria and Red Rubin housing 10 fry and 2 bladder snails
55 gal with Oscar (future planted tank with angels and flowerhorns)
55 gal Community tank (platys, mollys, guppys, glass catfish, angels, phantom tetra, red eye tetra and swordtails)