Hey all,

I just got myself three 150W MH lamps, which I'm looking to incorporate into a canopy. My tank's a 4ft.

My question is, how high off the water surface would these need to be? I have plenty of computer fans and the canopy will have an open back so I'm not too fussed about heat around the lights, just the radiant heat from the bulbs being too near the surface that might kill any livestock.

Thanks guys

i think i run my 250W MHs around 22cm from water surface and they could go closer, so 150W should be able to be closer than that

Wow that was fast

That's good news because I went to redwood aquatics and had a look at their MH pendants to see if there was a recommended height and one of them said at least 30cm from water surface. That plus the depth of the lights would make for a pretty fugly canopy

Oh yea also, do you think I should bother getting T5's for bluer lighting? Sigh, I'm too poor to even consider this hobby, and I've yet to see one fish!

what spectrum are your bulbs?

I just ordered 14000k bulbs because I read that they've got a balance of blue and white?

T5s are nice to simulate the dawn/dusk light, lets you see some of the night critters come out too (plus i actually prefer the look of the blue lights)

Hey all,

I just got myself three 150W MH lamps, which I'm looking to incorporate into a canopy. My tank's a 4ft.

My question is, how high off the water surface would these need to be? I have plenty of computer fans and the canopy will have an open back so I'm not too fussed about heat around the lights, just the radiant heat from the bulbs being too near the surface that might kill any livestock.

Thanks guys

Oh, around 75mm or so should be enough. It's not like the fish are going to swim under the light and then suddenly explode from the heat. The closer it is the warmer the water will get free heating over winter really...

Biggest thing is you don't want the cover glass getting splashed.