Whats the best light option for a 265g Planted tank?

[VRWC]

Im planning on moving my bichirs into my 265g (7'L x 2'W x 2.5'H) and would like to have an abundance of low light plants (basically pack 75% of the tank with them). I dont plan on using c02 and dont plan on using ferts either...just good lighting to help growth. Is this possible? Im not looking for tremendous/ speedy growth as the plants are all around 2 ft now anyways.

Should I go MH or just use the standard 6500k hydroponic lighting?

Ive read that in tanks taller than 24", Id need to go about 5w per gallon. Any truth to this and does anyone have any experience with growing in taller tanks?

My personal view is that Ill probably need about a 200w metal halide.

Thanks for any help!

 

[jcardona1]

Unless you're trying to grow an algae farm, stay away from MH and T5HO. For a non-co2 tank, you'll do just fine with T8/T12, PC, or T5NO fixtures. And also, don't rely on the wpg rule, it's useless and incorrect. Check out the Lighting sticky. Lots of good info there.

 

[ar0wan]

wpg is still a decent estimator for T8/12..
It's the newer technologies that screwed it up

 

[jcardona1]

wpg is still a decent estimator for T8/12..
It's the newer technologies that screwed it up

True, T8/T12 is okay. But still doesn't take into account PAR vs tank depth, which is more important. That's why the trend these days is to rely on PAR data as opposed to wpg.

 

[ar0wan]

you are boarderline OCD
which is fine cause so am I

 

[jcardona1]

you are boarderline OCD
which is fine cause so am I

HAHA, I've been called a crackhead on several occassions! But seriously though, this is why WPG is teh suckage:

Two tanks, a 20g Long and a 20g Tall. Both hold the same amount of water and based on the wpg rule you'd have the same light over each, right? BUT, one is 4" taller than the other. The 20g Long will have a lot more light intensity than the 20g Tall. 4" can make a big difference in PAR. So while they each have the same amount of light according to the wpg rule, the plants in the Long tank will be receiving a lot more light, and depending on the fixture used, maybe even too much light - which could potentially give you algae problems.

 

[ar0wan]

Once again you are backed by facts, examples, and experience

Doing It Rite, thx j

 

[JasonG75]

Unless you're trying to grow an algae farm, stay away from MH and T5HO. For a non-co2 tank, you'll do just fine with T8/T12, PC, or T5NO fixtures. And also, don't rely on the wpg rule, it's useless and incorrect. Check out the Lighting sticky. Lots of good info there.

TOTALLY agree, you don't need 5wpg or T5 to maintain healthy low light plants. If you throw this type of lighting on this setup you WILL have to go to Co2 to help control the algae.

 

[VRWC]

Nice. Thanks for the info. Looks like T8 setups will be an ***load cheaper than MH as well.