Hamilton 250 watt 14K MH bulbs

Hamilton 250 watt, 14000k metal halide bulbs.

Test bed:

My 90 gallon reef tank, heavily skimmed, bare bottom, 24″ deep with a PFO ballast.

The good:

I bought a pair of Hamilton bulbs to replace some aging bulbs on my 90 gallon reef tank in September of 2009.  After the burn in, the bulbs produced a crisp white/blue color.  The green and orange colored corals had a nice glow under these bulbs and the brown and beige corals looked more detailed.  It also made the water look very clear and even though the organic waste in the tank was somewhat high, the tank did not look yellow.

The coraline algae grew like gangbusters.  I had more sheeting coraline algae growing than ever before.  It was covering my all of my live rock, the bottom glass and even my pumps have what looks like shelves of algae growing on them.  The coraline algae started to grow within a few weeks of installing these bulbs.

The bad:

For the first six months, the corals were opening fully but there was little or no growth.   Between the six and nine month mark the corals started to shrink in size to almost half or less.  The number of bright green and orange mushroom corals dwindled and the few that are left shrunk from silver dollar size to between quarter and nickel size and they no longer open up.  Since using these bulbs, again around the six month mark, an outbreak of aiptasia started.  I never had aiptasia in this tank before but suddenly I did then although I am willing to guess that the aiptasia was just coincidence and cannot be certain that these bulbs are what caused it.

Conclusion:

For a fish only tank with live rock or very low light corals, these bulbs would be perfect as long as they are replaced around the six month mark.  For a reef tank with soft corals that is 24 inches deep, I would not suggest using these bulbs.  Even though they look great, they do not have enough intensity to support the less light demanding corals that I have been keeping for the last couple years.  They are much crisper than the 20kk bulbs that I have used in the past but they just aren’t working the way I had hoped.

Overall:

Great looking, awesome coraline growth, short lifespan and not enough intensity to support coral growth.