redearslider.com

I noticed that whenever I drop calcium blocks i get from pet shops into the tank my RES will go near it and the tiny specks from the block goes to his eyes. He rubs his eyes a lot when he tries to eat the block (is he even supposed to eat it???? :? )

If you want to provide calcium for your turtle, your money would be better spent on cuttlebone. It's found in the bird section and it comes with a hard backing on it that has to be peeled off. Other than that, break it into small pieces and let your turtle eat it. It can help reduce begging, plus it is nutritional.

Turtles can eat the calcium blocks but, as Missi said, it would be cheaper getting cuttlebone.