Par38 help

[aljan]

i have a shallow rimless tank of
L30xW25xH15". its mostly an anemone
tank. i have an rbta ive had for more than 4 months and has not lost any coloration. my lights are 3x Par38. they used to sit about 9.5 inches above the water, but this week i lifted it by 3".

so now my lights are 12.5" above my
water level and im wondering if others can give me advice as to the proper height i should have? i raised it up for more coverage and as an experiment. i was thinking it was too close.

any inputs are welcome, im open to adding more par38 bulbs if you guys think i need to also. thank you!

 

[Degener8]

With the distance to top of water I think yoru fine. The par should be ok at the bottom for LPS. I think you should spread your bulbs out a bit more.. hard to tell from the pic but looks like they are more to the right than centered for the middle one then spaced out evenly left to right for the others.
This would also explain the shadown on the left of the tank..

What optics are the bulbs using.. I would think 80 degree optics would be best for the tank with it being 25" wide hence the shadowing up front as well..
Hope others chime in as I am not an LED expert by any means but that is myh perception of what I see.

 

[aljan]

yes ur right sir, my lights are slightly to the right but looking from it sideways, its at the middle.

looking at it infront its more
to the right

and yes they are 80 deg

thank you for your input!

 

[johnanddawn]

i would get a 4th bulb and stay between 6 - 10" from the surface
80 degree will give you plenty of spread at that height. tighter optics like 60 could be 8 - 12" up and 40 even higher still
with PAR 38's - the coverage is best when kept to 1 square foot so a 24 x 24 tank would need 4 and your tank is a bit bigger the that