Last Lighting Question - I Promise!

[sacramonel]

Would a 400 watt Metal Halide be too strong for a 75 gallon tank. The depth ist 18 inches, i believe.

 

[Aquascaper]

I had 400w over a 4 x 2 x 2 and had issues with some corals that were close to the surface being 'burnt'.

IMO 400w over an 18" deep tank is excessive and won't leave any areas for lower light loving corals, basically the whole tank will be high light conditions.

The same units can be found in 250w models and would be much more suitable for your tank

 

[sacramonel]

I would be getting the 400 watt unit for free. If I suspended the unit 12-18 inches above the water and only had the unit on for 4-5 hours, would that be acceptable?

 

[Aquascaper]

Suspending a 400w halide 12" - 18" above an open top tank will cause massive light spill (trust me on this, I know) unless you enclose the light. Doing that however will cause temp regulating problems and increase evaporation, cause big fluctuations in sg and possibly pH as well.

It's do-able but is it worth it just because it's a free unit?

 

[Matthew5664]

Get the free unit, ebay it and get another one more suited to your tank?

 

[SkiFletch]

Get the free unit, ebay it and get another one more suited to your tank?

ding ding ding, we have a winner