Questions on Lighting for new 300 Gallon tank

I believe that 6700K is the common rating. Also the plants you have listed are low light plants and would probably be fine with your normal output single light strip.

God luck

That is a very low amount of lighting. I am not sure if anyone has even tried that low, atleast not that I have heard of, especially with a 30" tall tank. I am guessing you arent planning on using some nice polished reflectors to focus that light down into the tank either? As far as K rating goes just about anything will work, the K rating isnt all that usefull. But many stick to around 6700K and many also mix in something aorund 10,000K to add a bit of blue and make it look better to them. But anywere down to 3,000K and up to around 14,000K has grown plants well.

I would just use off the shelf grow lights under those circumstances. Except for the Sagittarius I have grown those plants with very little light. It is a great way to grow diatoms. The green algae usually can’t handle it. The problem is that nothing is really growing all that much.

A lot would depend on how much ambient light the tank would get. With a little more ambient light the green algae will grow and the diatoms will die off. That is kind of an easier problem and it usually means there is enough light. Some kind of regular fertilization routine would help too.

That's going to be an expensive tank to light, wow.

For a budget i'm a big fan of T8s on a decent electronic ballast. You can buy really good electronic ballasts for typical wattage bulbs for like $10 at ..

you know what, this is rediculous.. you would need a ton of them, you couldn't pay me to wire all of that, heh.

Just to get 1 watt per gallon, you need at least that IMHO. You're looking at 0.5WPG right now, that's like trying to grow plants under a single 20W light in a 55G aquarium. Of aiming a lamp with a 100W incandescent on a 55G, it's just really really low.

You would need 10 T8s, or 5 of those electronic ballasts. decent bulbs are 3 bucks each at a hardware store and the ballasts are $15 each (get a good electronic for T8s), only $2-3 for the endcaps.. but it adds up when doing that many bulbs, plus it's a stupid amount of work.

Here is your answer:

Two of these if you want moderate lighting: http://cgi.ebay.com/400-Metal-Halid...ryZ46314QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Two of these if you're fine with low lighting: http://cgi.ebay.com/175-Watt-Metal-...ryZ42225QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

These lamps are just as efficient as fluorescents. Trying to get to 1WPG with a flourescent is crazy, you'll have just as much heat as you would with a couple of these with much, much more work involved..

175s will fit under a canopy no problem.. and I'd feel safe sticking two 400s under a canopy on a 300G if the ballasts are remote ballasts (I think they are). Remember, WPG works for heat too, it's still only 2.6WPG. The bulb itself wont cause any heat problems for your tank.

Forget about VHOs, they're about half as efficient as a NO bulb. When you overpower any fluorescent bulbs (includes HO/VHO in most situations) the point of diminishing return really hits hard.
You're looking at about 47 lumens per watt with a 48'' VHO and about 84 lumens per watt with a 48'' NO T8.

T5 HOs are about the only overpowered bulb I would ever consider.. ever.. They're extremely efficient and take up little space but they can be pricey.

Metal halides produce about 80lumens per watt for a typical inexpensive setup.. the spotlighting can be undesirable though, especially on those long tanks (96''? nice). You know, thinking about it for a bit if I had your tank and wanted moderate lighting (and had lots of money to blow ) , I'd buy 4 of those 175W metal halide retrofit kits instead of two 400Ws, you would be able to distribute that lighting pretty nicely.

I'd just like to add that most NO floruescent bulbs actually are more effecient when overdrivin, some actually peak effeciency at 4X. But the HO ones are already at about thier peak already. But like ErrorS said it would be a pain to wire up all those bulbs and ballasts. But its probably going to be a pain however you do it, and pricey for anywhere close to 2wpg. I will be setting up a similar tank shortly, and the light decision is killing me and my wallet. But I accepted that any tank this size if setup for heavily planted tank is going to be expensive.

isn't the WPG rule tossed out the door on large tanks??

I wouldn't say 'tossed out the door', maybe not as accurate as with small tanks but it still gives a pretty good idea.

I much prefer lumens per cubic inch of water.. but everyone seems content with watts per gallon (which is garbage.. even fluorescents range from 40lumens to 120lumens per watt)

If you are going to use only 4 x 48" bulbs, you could overdrive them. Believe me, they are bright. You get about 1.7 times the light out of an overdriven T8 bulb.