Confused about T5 lighting

[Lateralus_]

I have a 40GAL setup with 2x24" 24W T5's, PowerGLO i think (they came with the tank), looking to replace them as I have no idea how old they are.

My tank it fish only for now, might add a bit of coral in the future but I'd go LED if I really start adding coral.

My question is: how do I choose a T5 bulb, so many options, Blue?, Coral growth?, 10,000k (i dont even know the difference the "k" makes), also, what are some quality brands out there.

I basically want a light that makes the colors of the fish pop the most, not as concerned about coral growth.

Any constructive help/input would be appreciated.

 

[RocketEngineer]

Lets start with the basics, K value refers to the Kelvin temperature of the bulb. If you took a piece of metal and got it to 3500 degrees K, it would emit the same color as a 3500K bulb. The higher the temperature, the more blue the light.

Most folks use a combination of bulbs with the result being somewhere between 10,000K and 20,000K. Personally, I like the lower end of the scale with just a touch of blue so I use a combination of two 10,000K bulbs, a 20,000K bulb and an actinic bulb.

For your setup with only two bulbs, I would use a 10,000K and an actinic. The nice thing about T5 is you can mix and match if you don't like what you have a lot easier than other kinds of lighting.

HTH,

 

[Lateralus_]

What about 2 of these?
http://www.theaquariumsolution.com/t5-lagoon-blue-powerchrome-bulbs

they seem to be a good mix of high and low from what I'm reading. 16-17,000k?

 

[Lateralus_]

Also, does low kelvin promote more algae growth? Concluding that high kelvin would give less growth?

 

[cloak]

Check this out.

https://www.youtube.com/watch?v=6OSS_PoUX6o&feature=youtu.be

HTH.

 

[RocketEngineer]

That's one option. I like two different colors rather than two bulbs of one middle road color. To each their own.

 

[Mark9]

Just my opinion, but I don't think you have adequate light.
You should have 4 bulbs.

Here's ATI's recommendation for a 4 bulb setup.

16K - 20K - Bluish white with a noticable blue and red under-tone
4-Bulb combination
3 ATI Blue Plus
1 ATI Purple Plus


12K - 16K - Cool white with a noticable blue and red under-tone
4-Bulb combination
2 ATI Blue Plus
2 ATI Coral Plus


10K - 14K - Crisp white with just a hint of blue
4-Bulb combination
2 ATI Blue Plus
1 ATI Aquablue Special
1 ATI Purple Plus

 

[Lateralus_]

Good info, thanks.