RedDelPaPa

Hi all.

I have a lighting question maybe some of you plant growing guru's could help me with. Right now, I have a 75gal all-glass tank with an all-glass twin tube strip light. It has 2 40watt full spectrum tubes. Right now, my plants seem to be doing ok, but I'm not injecting CO2. Is this enough light for a non CO2 tank? Or would I see further improved growth by going with more light?

And if the answer to my most recent question is yes, would I get more lumens by going with a triple tube fixture with 3 32watt T8 bulbs over the twin 40watt T12 fixture?

Thanks for any help,
Red

turbomkt

Actually, I'd go with two or three T5's. That's about 165W of light with three, putting you at a bit over 2wpg. At that point you can either go with or without CO2.

--Mike

RedDelPaPa

How do you figure?

Are you talking about using a Power Compact fixture? Cause I was just talking about a basic all-glass strip light fixture. Either twin or triple tube.

Simpte 27

You'll get more lumens out of the T5 fixture but I don't think that would be the way to go. I'll go out on a limb and say you're probably looking for 2-2.5wpg of good lighting over your tank. Thats roughly 180-200 watts over your tank. T5 lighting is expensive vs power compacts and or MH. FOr the price of a twin T5 fixture you could get much more out of a PC fixture.

RedDelPaPa

What's the difference in the T-series? 5, 8, 12, etc. Isn't is the diameter of the lamp?

MatPat

The "T" rating for flourescent lamps is their diameter. Lamps are measured in eighths of an inch so a T-12 is 1/2" and a T-8 is 1" diameter. The smaller lamps are more efficient and generally put out more lumens per watt than the larger lamps.

I have to agree with Simpte on the T-5's. I think they would be great on a CO2 tank but it may be overkill since you don't have CO2.

If it were me, I would probably get another double strip light and keep the wattage at 160 watts on the tank. You will get better coverage on your tank (front to back) by using standard flourescents. You could use dual PC strips on the front and back if you were going to use CO2.

If you decide in the future to upgrade your lighting you already have two 4' housings that you could put some AH supply lights in.

Even better would be to swap out the ballasts and try overdriving some T-8's in the existing fixtures. T-8 lamps will fit in the T-12 holders so all you would need is the ballasts at around $20 per ballast! Home Depot sells some Philips 6500K, 90CRI (Either T-8 or T-12) lamps with a good lumen output for about $6-7 for two bulbs. Can't beat that price!

If you're interested you can do a search both here and on Google for ODNO lighting. Reef Central has a massive thread on ODNO. That is how I did lighting on my tow 55's.

You may get a better response by posting your lighting question in the lighting forum next time

Avalon

Hold up there! T-5's are only slightly more expensive than PC's, and in the long run, they may actually be cheaper. Metal Halide is far more expensive than both, like double the cost. If you're a smart shopper, you will know where to find the deals. If not, let me help you out: http://www.specialty-lights.com. Retrofit's are slightly more expensive. The fixtures are only more expensive if you purchase the aquarium model. The other "plant" model is the exact same thing, and with free GE Starcoat bulbs (The CSR actually recommended the cheaper model)! I know, that's what I bought.

The WPG rule does NOT apply with T-5's. The 4x54w model will knock the socks off of a comparable 4x65w PC fixture or DIY application. I have the 4x54w model over my 75g, and it's too much light!


Back to the original question at hand, I would go with 4-40w NO flourescents for a 75g low tech tank. That would be just right, and would grow a wide range of plants. I had 4x40w NO flo's on a 100g, and it was barely adequate, but plants did grow...oh so slowly.