I have found that the color of the sand totally affects my rays, and I am finding that Lighting too has impact on my rays color.
For example, my motoro's get so dark on black sand that it is hard to to see any patten or spots on the but when put on light/white sand there patterns and color really come vibrant,
Leos on the other hand for me on the white sand made there white spots become really bright white from have a little yellow shading when they were on black sand ( I have heard that feeding only fresh prawns will have the effect of making the white dots turn a slight yellowish shade and I was only feeding fresh prawns at the time ) Also the black on the leo's did fade to a dark steel gray color on the white sand.
Now for lighting, as of recent I had to replace few bulbs that burnt out so I decided to replace all the bulbs on two of my tank from 6.7k to 10k bulbs and as of so far I really really am pleased with how my rays look under them. The leos really look great and seem that there white spots have become very vibrant and this is on black sand and my Xingu's really look amazing now, before they looked pale and not very definded even yellowish or pinkish shades to them but not no more.
Now they have been many varibles to my results. The biggest one being stress on the ray and its effects and saying that I never tried to put stress on my rays, only times i moved rays from one tank to another was because of aggresion or because of separating males out to give females a break from breeding. The one time I did decide to change the sand color in my tank I got stung, So serves me right for pissing around in they in envirioment lol.
Pic 1 Female motoro being moved from tank with black sand.
Pic 2 Female motoro pic taken yesterday.
Pic 3 Male Xingu earler this year natural light only.
Pic 4 Male Xingu yesterday 3 weeks under 10k lights added.
