MH bulbs for 24in tank? advice?
 

So I have a 180g 24in deep tank. I have 150w MH with 96w actinics.
currently i have 13k bulbs in the MH

What bulbs should i go with for the MH? 15k XM? 20k XM? 14k phenoix?

I like more blue than white. I hate it right now when my MH are on, I like it better when the actinics are on.

im keeping lots of sps.

Since you're keeping lots of SPS I would suggest the Phoenix because it will have better output than the rest. The XM 20K has really low PAR in comparison. Which 13K bulb are you using now?

+1 on the phoenix! 20k 150W won't give you great growth at that depth IMO. The phoenix actually look more blue than 14K. Again, you're welcome to come take a look at mine. I have the 150W phoenix with the same actinics as you.

I'm using 13k gie. (sorry not sure how to spell it)

Giesemann. You would find the Phoenix bluer, but also brighter looking. The Giesemann 13K is a nice bulb, but I prefer the Phoenix.

+1 on the warmer color temp. If you're doing light demanding livestock you'll want maximum PAR thats available from the warmer color temp such as 10k (especially considering the lower wattage MH bulbs). You can offset the lower PAR output of the cooler bulbs by getting the fixture closer to the water surface, just be aware of the increasing heat input as you drop below 12" between the water surface and the MH bulb. The 14k Phoenix is a good compromise between glowiness and PAR output.