Color Change

[fang06]

I recently got 2 reticulated stingrays from my lfs and have had them 3 weeks. Both have been eating well on ghost shrimp and moving around the tank. They are young one is 5 across and the is about 6 across. I have been doing 15% water changes every 3 days and have 2 power filters on the tanks with a 8x turn over. I was trying to move them to frozen shrimp and tubifex worms I gave them Tues. Wednesday the larger of the to lightened up in color.
The tank was cycled for 2 months (With 2 angels, a bala shark and 2 golden dojo loaches) prior to adding the rays and their only tank mate is a 5 inch black ghost knife. They are on fine sand. This tank is only for the first 6 months then they will be moving to a 75 with a fire eel. The tank is 40 but I wanted to make sure they are eating and healthy before moved in with the fire eel. He is young as well about 10 to 12 inches. The question is why would the ones color lighten up? I did a 25% water change and added Ghost shrimp last night they both went right after them and ate. Is there a problem I should be concerned about? Or do they just lighten up when they are comfortable.

 

[Miles]

From what I have noticed, Retics will lighten up a little bit when they are stressed.. Could just be a color variation, too. I have some that are really dark, almost black, some that are almost red, and some that are light beige..

I would constantly be testing for ammonia and be careful not to overfeed or have any uneaten food in the 40g.. any Ammonia or Nitrite will cause them to lose their color. A sure sign of stress is they are staying constantly buried.. but make sure your sand is ray safe - a LFS might tell you it's ray safe, but most LFS have no clue. Still eating is a good sign.

 

[Tommydeal]

I have three retics and when I first got them, one was really light colored and one was very dark. At some point the light one turned dark and the dark one's color got much lighter. Their behaviour didn't change one bit during this time and my water parameters were always 0-0-40, same diet. After a month or two they reversed colors again and have been the same ever since (6 months). So I don't think you have anything to worry about besides the fact that they are in a small tank. Like Miles said, keep a rigorous waterchanging schedule. I kept my rays in a small tank when they were very young and had no problems but I was doing a lot of waterchanges.