The amount of food your giving them seems extravagant. Turtles around a year old should be feed sticks every other day, one time a day, the amount that will fit into their heads. A variety a veggies/plant matter can be fed every day. Overfeeding the sticks(or foods high in protien) can lead to health problems.
Did you say a ten gallon tank? They really need an upgrade soon. The minimum size tank/container that they need is 10gallons per inch of shell. For your turtles right now if they are housed together they are in need of at least a 60+ gallon tank. When full grown you will need at least a 140 - 240 gallon enclosure for them. Adult males can be 7-9 inches and females can get up to 10-12inches, so it will just depend on their sex how big you will eventually have to upgrade to.
The lighting being on 12 hours is fine. I try to follow daylight hours so more in summer less in winter. You didn't mention a UVB did you, just a heat bulb? They really need a UVB bulb unless you take them out side for unfiltered sunlight 3-4 times a week for a few hours each time.
Sorry this is so long. I wanted to touch on all the points that I feel needs tweaking in your setup/routine seeing how you asked whether the way you were raising them was the right way in your first post. I know it's so easy to give in to them when they beg for food, but you will be doing them more harm than good in the long run if you keep this up. My turtle, Koopa gets 5 sticks a day and all the veggies he wants to eat. I try not to give in when I see him beg (which is about everytime he sees us). I know he will be better off for it. Occasionally I'll give an extra veggie or peice of fruit(like half of a grape) if he keeps up. But I know these aren't so bad for him as things high in protien that will cause fast growth.
Let me know if you have anymore ?'s.

I'm sure others will have some great input for you as well.