# How high should HQI be over aquarium?



## doubleott05 (Jul 20, 2005)

better question should be how high does amano put his? 

so im just wondering what people think is a proper height for HQI to be over the surface of the water. And why?

i do know that if your too close you get spot light effect.... too far and you loose light intenisity.. 
i have been using hqi since 2005 and was just wondering what others thought.

Thanks 
Elliot


----------



## SuperWen (Aug 26, 2010)

Referring to ADA catalogue 2011, amano hanging MH150W 40cm above water surface for 3ft tank to get highlight. In that book also explain we can hanging 30cm to get more light intensity or 50cm to get lowlight tank.


----------



## niko (Jan 28, 2004)

Yes you can find specific numbers in the catalogue. The idea is that the light spill is minimized - the light hits the top edge of the tank. It does not go over it and hit the floor.

But there is something more important. Just like ADA changes the filter media with the tank development you should think of the light height as depending on where the whole system is. I guess that is one reason ADA came up with the ugly hanging bracket for the halide light fixture - it's easy to move the light up and down.


----------



## doubleott05 (Jul 20, 2005)

hmmm thats a thought... change light with plant development. 

thanks
Elliot


----------

