They never supported them except for the 250's. And the warning about yellow has been around for years but honestly I've never had a problem.

I'm not saying run out and use Ushio's on probe starts, but just recounting my experiences with them. Theory is one thing but seeing is another.

I'm playing a game of mystery ballast myself at the moment. Fun isn't it.

Seeing as though they are ESU ballsts your best bet would be to ask them about it.

http://www.esuweb.com/knowledge/modules.php?name=Forums

So here's the $million question. I've never had MH lights before and this is a new tank. I plan on mostly softies and maybe some LPS. The fixture has 2x175w MH and 2x40w actinic. I think I would like bright, vibrant light (for myself, visually). There's 5 brands of bulb listed above. Which should I choose? :)

i would go xm 10k. if down the road you want to go with a bluer bulb you could try a 14k or 20k bulb but the 10k is a white bulb with lots of par for a 175. if you could find the iwaski 14k 175 they are claiming it is almost as bright as a 250 and closer to a white bulb that blue if you want more light.

c
 

Any specs on the 20K XM?

I never knew Iwasaki made anything above 6500K :eek:

Venture bulbs are most likely the cheapest ones out of the 4 listed. While I've never seen them personally, those who have them seem to like them. XM bulbs are nice and bright though. You need to be careful as there was supposedly a bad batch that came out a while ago that was prone to cracking :eek:

The XM 20000K is a blue bulb with very little par...that's what I've read so far anyway.

According to this site, the XM 20K has higher PPFD than the 15K, check near the bottom of the page, there is a comparison chart.

http://www.advancedaquarist.com/2005/6/aafeature2/view


I am also surprised that the name brand ballasts seem to get lower PPFD on average, than the "standard" magnetic M59 type ballast (not sure what brand "standard" is though!)

They've had an insanely blue bulb as a 150W size for a number of years which sounds neat but there seems to have been not enough interest to generate importing other sizes. They call it a "50000K" (although of course it's not really). I've always wanted to give one a try but have never gotten around to it. It's a medium base socket (not mogul or DE) though.
http://www.premiumaquatics.com/Merch..._Code=mh70-150

There is also this new one (14k) which looks pretty neat. Like Willow I want to try some of these soon:
http://www.premiumaquatics.com/Merch...y_Code=mh-175w

I'm with Willow on this one. You might want to start with a 10k and see how you like it. A "good" 10k should fit your description of a "bright vibrant" light (think "crisp white" or "white with a hint of ice blue").

A good 14k bulb isn't too bad either. I did try the venture 14k's though (in the 250W size) and I found them to be overwhelmingly blue (think disco blue). (Just my own preference, others may like it, but it was a bit of a culture shock for me coming off 6500K's). I ended up trading them in for some Venture 10k's and I am happy with the colour of those bulbs (I do have actinics alongside so that did influence the overall blue-ness). But in the past I've had other 14k lamps (in the 175W size) and found them to be a nice colour. I find 14k's are good all by themselves, but the problem is they tend to have a lot lower PAR. I have 10k's over one tank by themselves (Ushio 175) and 10k's over another (Venture) with actinics and I think I like the look of actinic supplementing slightly better. And you can have a cool dawn/dusk effect. But of course, it's all personal preference.

i called pa and asked what they thought of the iwaskai 14k's. jason told me they had one running on a tank and it was *very bright*. he said it was a shade bluer that a xm10k but not by much. if i was growing sps with 175's that what i would want i guess. my disply now is all lps and i was looking for more colour so i tried out the xm 15k. it really pops the colour out but time will tell if anything ever grows again.

Dang it Willow, I think you just convinced me to spend some $$$ that I was saving up for other things. I think I'm going to try these Iwasaki's. Oh well, worst case scenario, they won't live up to the hype but at least then we'll know. I'll let you know how they work out (assuming pa has them in stock right now I'm going to go order 2).