blueish looking lights

[Synatix7]

What are those called? cause when i upgrade to a bigger tank ima wanna get a cool light that will make the tank look sweet.

 

[Stryker]

The lights suitable for plants have a bluish mayby purple-ish tinge to their colour owing to the part of the light spectrum they put out.

However, There are also the tubes often called "moonlight tubes" (depending on manufacturer). They are tubes that use a part of the spectrum that enhances fish colour..... in fact they are always sold as fish colour enhancing lights.

 

[thecichlidaddict]

What are those called?

Perhaps you are thinking of Actinic lighting, used in reef setups?

 

[Lateral Line]

Actinic tubes usually require a more powerful starter then an ordinary tube. If you take out a 40W regular, and put in a 40W Actinic, it may well not run.

Any lamp which has a rating of above 6500K will have a bluish tinge to it. They are not very good for planted tanks though if you were thinking along those lines.