In the wild...
Video of family here
Crenicichla celidochilus, one of my favorite fish, is a headwater species from tributaries to the upper and middle Rio Uruguay. Their conspecific aggression is immense, but beyond a general dislike of other pikes as company, they are quite tolerant of other taxa (e.g. Gymnogeophagus). Their "lip spots" give them a very interesting (and of unknown function) ecological feature. They're one of the most colorful species found in the Rio Uruguay drainage (maybe some Gymnogeophagus and Leporinus amae are comparable). They have a strong affinity for rocky habitats, and also prefer habitat with a lot of heterogeneity (mixtures of pools and riffles). Specifically, they seem particularly fond of "dead" zones among fast flowing riffles and deep pools with rocky ledges or outcropping. Females are more colorful, with bright orange/red abdomen and red tint in the lips. Males can display an orange/red blaze down the flank, but is much more modest than females and more reminiscent of a "stripe" in contrast to females which entire flanks and abdomen can be brightly colored. Females also typically have more coloration in the dorsal, which can include orange-red-pink highlights and few iridescent spotting posteriorly. Juveniles of both sexes can possess a dorsal occelli (spot). Both sexes grow to 21-22cm in the wild. Specimen in "breeding coloration" of 15+cm can be observed in the wild, suggesting they reach maturity around that size. Indeed, my breeding pair spawned at 15 15 cm. In the wild, they are typically found alongside Crenicichla missioneira and Crenicichla minuano, and other rock-loving species such as Leporinus amae and Apareidon affinis. Despite their ill temperament, they can be kept in conspecific groups (of similar size!) Felipe Cantera once suggested they be within 6 cm of one another to coexist, and I've stuck strictly by that wisdom. It has been my experience that conspecific aggression is greater than interspecific. Furthermore, aggression seems to dwindle with age. I have a group of 5 that were raised together and they are now full-grown and coexist peacefully, but a strict hierarchy is well respected. Crenicichla minuano also make suitable company and are extremely intriguing in their own right. In any mixture... caves, caves, and more caves is the best strategy for successful husbandry. I often use large rocks across the substrate and the pikes dig their own network of caves. A driftwood tangle or 'stump' on one side, can offer additional or "less preferred" structure for sub-dominant individuals if they need refuge.
My journey with this species started in 2008. I have collected in the Rio Cuareim basin four times and currently keep 10 adults. A detailed article discussion of the diet of Crenicichla celidochilus (among other species) can be viewed here.