Nah don't have a scale lol I'm just paranoid they are not growing right but they get at least 4-8 hours outside in the sun a day and eat a whole mixtures of greens and spring mix but they won't touch grass or hay so in nervous lol
Try chopping up some fresh grass super fine with scissors and just keep mixing very small amounts with whatever other greens you are feeding. It will take some time for them to get used to it. Gradually increase the amount of grass, but don't be in a hurry. You can also get a product called "Salad Style" from Tyler at tortoisesupply.com. It is finely chopped Timothy hay and orchard grass hay. You just sprinkle some on top and get an instantly better diet for them. Don't worry too much about it though. In time your babies will eat everything in sight.
.... And go get a scale. You can find them at Target, Walmart or Sears. It's pretty cheap and a good way to track their growth.
Mine only want to eat grass when they are grazing outside. When I mix it in with the spring mix they pick out the spring mix and leave the grass and weeds. I have tried cutting it up small but it doesn't entice them to eat it. I figure that since I see them eat it outside that they will eventually get used to it and I have been cutting back on the spring mix. Keep us posted and make sure you put up some pics. also.