DO NOT DERAIL
Jardini have the reputation of being the bad guys of the arowana world. They can be very nasty and a lot of us have discovered the hard way that these guys should either be kept alone or tankmates should be seleceted with care. I would advise you not to introduce a jardini into a tank with a fish you dearly love. You may wake up in the morning and find it dead...
If you insist on keeping a jardini with tankmates it comes down to a case of trial and error. It may or may not work. Its that simple...but at the same time a pain. Obviously you will not want to risk any unecessary deaths. Don't lose hope though, there are cases where jardini have succesfully been kept in community tanks. The only thing you might lose is a lot of money and a lot of fish on the way to finding a combination that finally works. But im sure the feeling of accomplishment will be great
Jardini also have a reputation to suddenly become aggressive after they hit the 8 inch mark. This has been found out by a lot of hobbyists so do not be fooled into thinking your Jardini is one of the tankmate tolerant ones. You may find out that suddenly your Jardini has gone on a killing spree. It has happened before…
A few tankmates I would suggest are the giant gourami, peacock bass and clown knives. A few people I know have had this combination work for them. Basically just try to keep tankmates of a bigger size than the Jardini.
Another commonly asked question is if leichardti will tolerate tankmates. This is hard to answer. Once again a case of trial and error. I have had leichardti beat up 12 inch + fish. In my experience they can be just as nasty. I have seen them in large community tanks though so who knows.
Source: http://www.monsterfishkeepers.com/forums/showthread.php?t=23838
