[jshaffer740]

I've read many of the existing threads about PAR and classification of low/med/high, etc. But I was hoping I could get some definitive (I know, there's probably no such thing) opinions as to whether my setup would be considered medium or high lighting.

I currently have a 37g tank - 22 high, 12 deep, 30 wide. The distance between my lights and substrate is about 20" in most areas (some are closer). I have a Aquaticlife T5HO fixture, w/ two Aquaticlife T5HO 24w (24" long bulbs). One bulb is the 6500k, the other is the 650nm "rosette" bulb (will probably replace). The fixture seems nice, with good reflectors (i.e. I can see about 4-5 images of each bulb in the mirrors).

I would like to be running a high light setup, but I'm just not sure if it is one. According to the chart at this thread: http://www.plantedtank.net/forums/showthread.php?t=184368, 4 Aquatic life 24w bulbs are around 110ish PAR at my substrate distance. Can you simply divide that in half for two bulbs? (My gut says no).

If I need to get different bulbs I purchase them, but I would like to avoid that if I can.

If anyone has comments, please jump in.

Thanks!

 

[Hoppy]

You should get about half the PAR with a 2 bulb light instead of a 4 bulb light, but possibly a little more than half. Until someone measures the difference in PAR between the roseate bulb and a white bulb I have to assume they are about the same. You have what I would consider to be medium light.

 

[jshaffer740]

Thanks Hoppy. If I wanted to get to high light, are there different bulbs I can swap out that would get me to the PAR I need? Or does it require an additional fixture?

Thanks!

 

[chunkychun]

i'm using the 18inch aquatic life for my 18 inch x 18x18(about18inches from substrate). Originally i had just one (two bulbs same as yours) and I felt I was getting low light. got a second set and now running 4 total bulbs(2 rosette and 2 6500)and also got par meter and with 4 bulbs it was around 50-60. i think you would need 4 bulbs for your depth and tank size to run med/high light.

I'm not sure why i'm getting such a different result from the chart(which i used as well). I guess it is the rosette bulbs.

 

[jshaffer740]

So I should add another fixture (they are linkable, which is nice), and perhaps ditch the rosette? Would that get me to high light? I hope so, as I don't know if I have room across the tank for more than four bulbs lol

 

[chunkychun]

i would just try the 4 bulbs that came with the fixtures and see how that works. if it doesn't work then try switching bulbs.

 

[jshaffer740]

Purchased another fixture today. I'll be linking them up and seeing how things go.

 

[briansbelle]

What part of Ohio are you in? Im in Ohio too