The end of WPG? How is this?

I want to get rid of watts per gallon, I'm sick of it. It just plain doesn't work anymore.. MHs can be anywhere from 70 to 110 lumens per watt, incandescents and halogens can be from 10-20lumens per watt and Fluorescents (HO, VHO, NO) can be anywhere from 45 to 130 lumens per watt. That's a huge range.. just in commonly used bulbs for aquariums you can go from 70 to 130 lumens per watt.

It's horrible.. I could tell you I had 6WPG of VHOs on my tank, which sounds really really high, but it's only outputting the light of 3WPG of normal output fluorescents.

It's simple enough..

just lumens divided tank (depth*2) + tank width + tank length. It's very simple, based on lumens per gallon except it stresses the tank height more.

In other words.. you multiply the depth times two, then you add this number to the width and length and divide the lumens with it.

So for 10K lumen output on a 55G tank it would be: 21*2 (42).. 42+12+48 (which would be 102), then you divide 10,000 by 102 to get the value you need.

Below 50 is very low lighting - (fish only)
50-150 is low to moderate lighting - (Fish only or lower-light plants)
150-250 is moderate to high lighting - (typical planted tanks without CO2)
250-350 is high to very high lighting - (Good reef tanks or heavily planted)
350-450 is very high to extreme lighting - (the best reef tanks or extremely high light plants)

This is for 10k Lumens, about two 55W power compacts.

72x25x25 - 180G-(tank is 147) - 68
48x24x21 - 75G - (tank is 114) - 87
48x12x21 - 55G - (tank is 102) - 98
30x12x30 - 46G - (tank is 102) - 98
30x12x12 - 20G - (tank is 066) - 155
30x12x18 - 29G - (tank is 078) - 128

As you can see, the 46G, even though it has less volume requires just as much lighting as a 55G.

Now, if it was 20k lumens which is a good value for a 55/75 moderately planted aquarium (This is about two 175W MHs average.. or a bit less than four T5 HOs), you wuold have these numbers.

20K lumens is about what people seem to shoot for in a 20L reef and you can just get by with this amount in a 29G reef.

72x25x25 - 180G-(tank is 147) - 136
48x24x21 - 75G - (tank is 114) - 175
48x12x21 - 55G - (tank is 102) - 196
30x12x30 - 46G - (tank is 102) - 196
30x12x12 - 20G - (tank is 066) - 303
30x12x18 - 29G - (tank is 078) - 256

Most bulbs vary only a small amount in lumen output.. even full spectrum bulbs, for the 5000-6000lumen bulbs (T5 HOs) it's only a matter of 500 or so lumens lost to get some of the invisible spectrums for your plants, which doesn't mess up the values above..

or the equivilent of one 48'' bulb or one of those 40W screw-in CF bulbs, about 3000 lumens.

72x25x25 - 180G-(tank is 147) - 20
48x24x21 - 75G - (tank is 114) - 26
48x12x21 - 55G - (tank is 102) - 29
30x12x30 - 46G - (tank is 102) - 29
30x12x18 - 29G - (tank is 078) - 38
30x12x12 - 20G - (tank is 066) - 45
24x12x12 - 10G - (tank is 060) - 50.. and as you know, one screw in CF is about enough for low light plants in a 10G, most people fit two, which would simply double this number making it 100..

So, will this work? Or can anyone find anything wrong with it? I thought the numbers worked out very well.

I don't like lumens per square inch because it doesn't take into account depth.. it is absolutely no different than lumens per gallon, the number will always be the same.
There is one near fatal flaw with lumen per square inch.. a 46G tall would, by the lumen per sq. inch rule, need LESS light than a 46g long.. but as everyone knows you will most likely need more because of the light penetration problems. (referring to this method: http://woo.gotdns.com/Aquarium/Lighting.htm)

and numbers for levels (low light vs. high light) will need to be tweaked with mine.. I don't know exactly what people shoot for with different aquariums, 10k lumens might be alright for a 55G.. I just feel like my 14k lumens on my 55g really need upgraded asap.

As a matter of fact, lets just turn this into a discussion about the WPG issue. If people don't like mine, fine.. lets find one that works. Lets just stop this WPG garbage

what I want most is a rule for all aquariums.. wether it's a small beta bowl a 48'' aquarium pillar or a 500G custom tank and if I'm not mistaken, my method will work for it.

phanmc, you're right.. but there's nothign that will work for everything. I do think Lumens are more accurate than watts.

This is suppose to be a general guideline, not a rule. Obviously, distribution, type of bulbs, etc will still be taken into account. But for the new user and as a general guideline, I can't think of a better way.

and I don't know of any plant bulbs whit that big of a difference? For 48s I see them from 2200-3000 lumens, that's still a small margin of error considering the alternatives for measuring.