Ok, here's what my tank looks like:
Koopa's Tank
You can look in the Photo Gallery for more ideas.
You need two lights. A heat light (which can be a regular household bulb in a clamp light) and a UVB bulb that emits 7-10% UVB rays. The basking area should be where the turtles can haul completely out of the water and dry off while basking under the lights. There shouldn't be anything between the lights and basking area to block or filter out the UVB rays such as plastic, screen or glass. Natural lights from windows and such will not help at all.
Do not feed the krill or shrimp more than once a month. It's too high in protein to be used more often than that. A reputable pellet such as Baby Reptomin should be used daily the amount that would fit inside their heads if they were hollow. And only once a day. You can use the shrimp or krill to entice them to eat now since they are adjusting to their home, but once they start eating switch back to pellets.
A submersible water heater is a must if you don't have one. Their water should be at 78 degrees constant for hatchlings with the basking temperature around 88-90. Get a thermometer and measure both temps as this is extremely important to their health.
They need as much water as you can fill the tank without giving them room to escape. You'll also need a good filter rated 2-3x's the size of the tank(filters are rated for fish not turtles - turtles are much messier). Get a basking area that will float with your water level so you can fill the tank.
Having happy, healthy turtles is very important which is why you should really look into setting up their habitat correctly as soon as possible. Remember that as your turtles grow their home must too. Ten gallons of tank per inch of turtle is the minimum they should have, so look into upgrading your set-up as soon as you can.
