Need your advices/suggestions on my 55 gallons tank for medium light.

[joedirt]

Hi Everyone,

I have couple questions relate to lighting. Base on the chart That was created by Hoppy (Thanks a lot), if I use 2 T5 HO 12 inches above the top it would give me medium.

Does it matter how many watt per bulb? If I use:

1. 2 T5 HO 54w (6400k and 10000k)
2. 2 T5 HO 28w (...)
3. 2 T5 HO 39w (...)
4. 1 T5 HO 39w + 1 T5 HO 28w
etc...

It would not be the same am I correct?

I would like to get medium/low for my 55 gal tank (48Lx21Hx13W). I want to get best possible light combination without using the CO2.

I plan to get 2 T5 HO 39w and hang 4 inches above the tank.

I have been reading for last couple days on lighting and I do have some ideas but I'm still not 100% sure. Any expert out there please give me advices/suggestions I would really appreciate.

This is my first post so please forgive me if I make some mistake.

Thanks

[Hoppy]

The ends of the tank will be less well lighted if you use other than 4 foot long bulbs, 54 watt bulbs. The 24 inch long bulbs, 24 watt, will very likely give less light intensity right under the bulbs because they will be so far from the substrate vs their length. The 36 inch long bulbs, 39 watt, should give about the same intensity directly under the bulbs, but a bit less at the ends of the tank. The only advantage of the 3 foot long bulbs is the reduced light spill over at the ends of the tank, when the bulbs are that far above the tank.

The actual light intensity, PAR, that you get also depends on how good the ballast is and how good the reflectors are. There are some big differences between some of the real cheap lights and the better ones.

[Yankee]

If you refer back to Hoppy's article be cites that after a certain bulb length (I think it was 24"), Watts become otherwise irrelevant and instead become a measurement of length. Now unless you can find T5s that are 48" long and 24 W vs 48" long and 54 W, that can be a different story since the output is increasing and not the length (like the case is for just about all conventional aquarium tubes). Just stick with 2 48" bulbs (54W) and forget everything else. They should be between 6500-10000K. A 2 bulb fixture over your standard 55 that's 4" above the top will need CO2 and will allow you to grow just about every plant.

[joedirt]

Thanks a lot for quick reply guys.

I thought T5 HO 48" 39w (or 28w) are exist. I guess I looked at T5 NO.

I much more understand now.

In my case should I get 2 T5 NO (or 2 T8)then? Again I don't want to get into CO2 yet. 2 T5 HO 54w seem too much light for my tank. I could only move it up 6 inches above the top of the tank.

Thanks

[Yankee]

Originally Posted by joedirt

Thanks a lot for quick reply guys.

I thought T5 HO 48" 39w (or 28w) are exist. I guess I looked at T5 NO.

I much more understand now.

In my case should I get 2 T5 NO (or 2 T8)then? Again I don't want to get into CO2 yet. 2 T5 HO 54w seem too much light for my tank. I could only move it up 6 inches above the top of the tank.

Thanks

If you don't want to use CO2 then get 1 T5HO (54W).