Do I need a valve on sump plumbing?????

[windcoast reefs]

Im not fully sure what type of system it is called. But I have elbows facing up that attach to the bulk head for the drain and the return. For the Drain it leads into a t joint with a cap on one side with a small hole to stop the gurgling and then drains down to the sump on the other side.

Thanks for the advice, I will put a valve on both the lines.