lighting 7 inches above the water or directly on the glass?

[candymancan]

I have a 44g Pentagon.. that im messing with and I have a Orbit 2x 65w Power Compact light. Its 22 inches long the tank is 30 inches long and 25 inches deep. So the tank has a lot of girth making it hard to get light in every spot of the tank.. I have the light along the length of the tank and in doing so the very back corner of the tank is kinda dark but if I position the light differently then another spot of the tank is dark.. So I just put a T8 light fixture in the back to keep it lit up.

Now the Orbit fixture has legs that raise it a good 6-7 inches above the water line. I can take those legs off and lay it directly on the glass.. But im wondering what would be better for lighting the tank ? Would raising it be better to spread the light more through the tank... or would putting it against the glass be better ? I noticed raising it lowers the light level in the tank by quite a lot and lowering it makes the tank a lot brighter.. but im sure the light spread throughout the tank isn't as great laying down vs standing up..

I just dunno what to do lol

 

[BBradbury]

Your Tank Lighting

Hello Candy...

If the light is designed to rest on the glass, then that's the best place for it. You have a relatively tall tank, so you want the light to shine to the bottom. The longer the distance, the lower the intensity.

B

 

[candymancan]

Yea its 25 inches tall. I have about 3 almost 4 inches of substrate in there. And I noticed with the light on its stands the light is dimmer in the tank.. I can see the light spreading outside against my walls and stuff when its on the stands.. When I take the legs off and lay it against the glass its deff brighter in the tank .. Not as bright though near the top on the side due to how girthy the tank is.. SO I guess with the legs on it gives more light on the side and top of the tank, but lowerd on the glass its deff brighter in the middle and bottom of the tank.

I also took the reflector in the fixture and bent it to have more a ^^ for each power compact light.. Prior to that the reflector was like this /-----\ Now its like this \--/\--/ If this makes sense ? I was reading on those flat reflectors mine has with 2 lights and it causes the lights to drown themselves out between eachother and they lose like 40% intensity because of that. So with the bend in the middle between the lights I noticed the light is way brighter in the tank now. Basically they have individual reflector's now