Need help Geting my camera to shoot what I see in tank

[jeppley84]

Hi have a Nikon d90 I have a portrait lens 50mm 1.8f just wondering on what kind of set up I could use to pick up night time lighting when blues greens and reds pop. I can't seem to take a picture to what I'm actually looking at

 

[IslandCrow]

It's best to post an example, and we can help you from there. In the mean time, I'd highly recommend reading the stickies in this forum.