I want to try my first HQI MH light for a planted tank. I have an opportunity to get one of the Aqua Medic Ocean Light 1x150 setup's [example] from an acquaintance very lightly used.

I have no direct experience using an MH, or pendant style, but I reason that I can adjust the height to get even light coverage of a tank. That said, what size tanks would it work for?

Also, considering it is 150W, could it be used over a smaller tank, such as 10, 20H or 29 gallon tank? Obviously high-light, but was not sure if 150W MH raised above the tank to get even(-ish) light coverage, worked under the "watt-per-gallon" rule-of-thumb.

Considering it's not a wide dimensioned light fixture, am I right in reasoning it would not be a great choice for a 20-long or tank wider than say 24" or so? This is COMPLETE guesswork on my part.

Lastly, any issue with using a 10K bulb on a freshwater tank, as far as plant growth is concerned?

I would greatly appreciate any input, feedback and experience to help me. Thanks!

-Jason

Hi Jason,

Please note that MH produce a lot of light, so be careful using it on a small tank... Also as you note the spread will still be more tightly focused than other lights. MH works well IMO for deeper tanks, not as well for longer ones as you stated. That is definitely true. If you hang too high you will lose a lot of light to the room in general and not hit the tank.

My experience is with a 24" 6' 180 gallon and I have 3X150w 6500k bulbs.

Works well for me as I try to use the shadows that occur in the spacing between the lights......Many fish like it there.......Also works well for plants that like the shade.

I started out with 14k bulbs and had excellent growth, but switched as the light was too blue for me and was very bright. I like the 6500k much better........I would assume 10k work well but might be a bluer tint as were the 14k.

Ripple effects with MH are very nice.....

Please hang so you can have the most adjustment possible. I have mine mounted 10" above the water, and can adjust from 3" to about 15".

Good luck. Nice looking fixture.

I did think it a bit humorous to consider a 150W MH over a 10 gallon equaling 15wpg! (NOT considering this per se, just for those who go for the higher and higher wpg's) :-)