Mine are relatively short term result, so take it as a YOY - 2 year note of grass pickerel with tankmates. I got them last summer and all are now 6 +"
Takemates:
Tank
20L
Other Grass Pickerel - (I have had 1 incident of cannibalism @ ~3.5" vs ~5.5"). I have maintained three similar sized in one tank (the 65 tall) for over 6 months duration.
40G Breeder I
Bowfin - Broke the back of the largest (the cannibal) pickerel. The G.P. has not healed perfectly, but is hunting & eating again in a 50G pond of bull minnows.
African Knife (2) - Rescued from the mouth of the pickerel and both are re-homed in different 40G Breeder tank.
Golden Shinners (4) - Two were eaten. Highly suspect the Pickerel. The other two remain and have spawned in the tank with the Bowfin still there.
40G Breeder II (Much too short of a timespan to go into the non-harassed inhabitants of this 40)
Weather Loach (2) - Were both devoured by Pickerel.
55G
Bowfin - Many minor skirmishes instigated by the bowfin. (Lengths are approximately equal)
Silver Dollars (3) - No interaction whatsoever.
Bala Sharks (2) - This is the only fish that has died in this tank since introduction. I saw nothing occur to be sure. The other is still there and considerably larger than the Pickerel or Bowfin.
Koi Angel Fish - This fish seems to stay closer to the pickerel and interact with it more than any other combination that I have tried. Strange, but body shape (like the S.D's) might be it.
African Knifefish (2) - No issues (yet) but again these are nearly full grown and larger than the Pickerel.
Tire track Eel - no interaction whatsoever.
65 G tall
Grass Pickerel (3) - Minor skirmishes over food, gets more serious with wiggler worms.
Salavini - Frequent light pestering of all three grass pickerels. (To re-home all three pickerels to larger holding pond within month so not moving the cichlid at this time)
Bowfin - Major mess at feeding time. Very troublesome and potentially dangerous aggression at feeding time.
Albino Senegalis Bichir - No issues
