Apologies all around to those who feel they are desrved. Merely pointing out that broad sweeping statement's as to nature and growth of the Jack dempsey are subject.
These fish were named after a Prize fighter, as opposed to a Ballet Dancer, and they have a well earned reputation as belligerent fish as they Mature, with all regards to the few who expierience atypical behaivor. Sure, there are more aggressive cichlids, but to consider this particular fish as shy or timid would not be the normal description of the majority nor the expierience's of same.
Growth that was asked about, is average one inch per month with healthy fish. Course genetics also comes into play, A fish, or five or six fish,,, from one spawn, may or may not posess genetics that would allow larger ,faster growth than other fishes from same spawn. Just like people,,there are some who are short,some tall,some heavy,some not so heavy.
For the majority of large cichlids, along with many other species,,growth can be accelerated by offering several small feedings each day while the fishes are young, with foods that promote said growth.As a result of these several small feedings,water changes should be more frequent, to keep dissolved organics and solids from having negative effect on water qualtiy and subsequently having negative effect on fishes health (immune system), and growth.
Color's of fish as I described could be defense mechanisim with dominant fish displaying more color or,,,could be due to acclimating to new surroundings or water chemistry. Could take a few day's or a few weeks.
Lighting,substrate,are also factors to consider. Bright lighting can cause color's to wash out, and bright colored substrates can also result in lighter colors on fish as they try to blend with their surroundings. Hope to have been helpful rather than appear combative and again,, my apologies to those who feel they are needed.
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