I disagree, it is found naturally in many things, in the wild the diet of many fish will provide the anstaxanthin that will make thier reds vibrant, if the red areas are naturally red but the fish doesnt have enough natural red enhancers in the diet they will fade as the fish cannot produce reds naturally on its own. If the markings are just faded it may bring them back before it effects the main body color. If the fish lost the markings due to the patern changing with age then nothing will bring them back. Even if the fish recieves to much of the red enhancer and starts to turn pink it will fade away in a few weeks once it is not used anymore. Feeding in moderation will enhance any naturally red spots without causing unatural red coloration.
It is used in large amount for red dragon flowerhorn, half the body is red the other half white when used correctly the red half becomes more vibrant with no effect on the lighter half, when over used the lighter half will slowly begin to start showing slight color but first in the eyes and fins.
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