XM bulbs
- Thread starter fishy7
- Start date
rgf1046
Member
I have used the 15K 175W XM's for the past 2 years and really like the color. Since I am relatively new (3 years) to the hobby, maybe SCSInet could expand on why he is disgusted wth them, and maybe that will lead me to a better option when it comes time to replace them in February.
scsinet
Active Member
The 15K XM lamps are among XM's worst. They have terrible PAR.
I did a lot more research after I bought the lamps than before (yeah... dumb). My research led me to the Radium 20K, which IMO is a similar color to the XM15. I bought the Radiums and installed them and the amount of difference was insane.
Google searching (Try the "Sanjay's lighting guide") will yield lots of data on how good the Radium is and how crappy the XM is.
I did a lot more research after I bought the lamps than before (yeah... dumb). My research led me to the Radium 20K, which IMO is a similar color to the XM15. I bought the Radiums and installed them and the amount of difference was insane.
Google searching (Try the "Sanjay's lighting guide") will yield lots of data on how good the Radium is and how crappy the XM is.
stanlalee
Active Member
Originally Posted by rgf1046
http:///forum/post/3159555
Do you think their PAR gives enough penetration for a std. 55gal (2 pendants)? It doesn't look like Radium offers a 175w single-ended option, that I could find anyway.
175w XM15k have enough PAR for a 55g. They basically have roughly the same PAR as XM20k (which is a decent performing 20k lamp) give or take an insignificant amount depending on which watt bulb your talking about. The problem is you expect a 15k XM to have significantly more PAR than the 20k. You basically are sacrificing color with no benefit in intensity so there's virtually no reason to pick the XM15k over the 20k. If YOUR happy with them just keep them until its time to change them out and try something else. I talked to XM and they have a new 15k bulb that they claim has class leading PAR. it should have been out by now (they said first quarter of 2009) but I havent heard anything all year.
As far as 150w DE bulbs I use ushio 20k and aquamaxx 14k and have been pleased with both. for a 20k like blue bulb I see no need to deviate from the aquamaxx. the price to performance ratio cant be beat and they look just like radiums (PAR unknown as of yet but I've had em long enough to know they perform well). I paid $60 for two (B1G1F sale) and even at regular price I could get 3 for the price of 2 radiums. I'd pay more for the Radiums if they had significantly better color (which I know they dont) but not for PAR (which I dont know but assume the radiums have more). the ushio's are a different shade from other 20k bulbs, if you like a more actinic purple/white then blue/white these are it. I'm thinking about going white and getting AB13k (I had them in 175w form). I kind of miss the crisp white look and they have twice the PAR of most 20k 150w bulbs according to sanjay testing.
http:///forum/post/3159555
Do you think their PAR gives enough penetration for a std. 55gal (2 pendants)? It doesn't look like Radium offers a 175w single-ended option, that I could find anyway.
175w XM15k have enough PAR for a 55g. They basically have roughly the same PAR as XM20k (which is a decent performing 20k lamp) give or take an insignificant amount depending on which watt bulb your talking about. The problem is you expect a 15k XM to have significantly more PAR than the 20k. You basically are sacrificing color with no benefit in intensity so there's virtually no reason to pick the XM15k over the 20k. If YOUR happy with them just keep them until its time to change them out and try something else. I talked to XM and they have a new 15k bulb that they claim has class leading PAR. it should have been out by now (they said first quarter of 2009) but I havent heard anything all year.
As far as 150w DE bulbs I use ushio 20k and aquamaxx 14k and have been pleased with both. for a 20k like blue bulb I see no need to deviate from the aquamaxx. the price to performance ratio cant be beat and they look just like radiums (PAR unknown as of yet but I've had em long enough to know they perform well). I paid $60 for two (B1G1F sale) and even at regular price I could get 3 for the price of 2 radiums. I'd pay more for the Radiums if they had significantly better color (which I know they dont) but not for PAR (which I dont know but assume the radiums have more). the ushio's are a different shade from other 20k bulbs, if you like a more actinic purple/white then blue/white these are it. I'm thinking about going white and getting AB13k (I had them in 175w form). I kind of miss the crisp white look and they have twice the PAR of most 20k 150w bulbs according to sanjay testing.
rgf1046
Member
Originally Posted by Stanlalee
http:///forum/post/3159664
175w XM15k have enough PAR for a 55g. They basically have roughly the same PAR as XM20k (which is a decent performing 20k lamp) give or take an insignificant amount depending on which watt bulb your talking about. The problem is you expect a 15k XM to have significantly more PAR than the 20k. You basically are sacrificing color with no benefit in intensity so there's virtually no reason to pick the XM15k over the 20k. If YOUR happy with them just keep them until its time to change them out and try something else. I talked to XM and they have a new 15k bulb that they claim has class leading PAR. it should have been out by now (they said first quarter of 2009) but I havent heard anything all year.
Great information, thanks!
http:///forum/post/3159664
175w XM15k have enough PAR for a 55g. They basically have roughly the same PAR as XM20k (which is a decent performing 20k lamp) give or take an insignificant amount depending on which watt bulb your talking about. The problem is you expect a 15k XM to have significantly more PAR than the 20k. You basically are sacrificing color with no benefit in intensity so there's virtually no reason to pick the XM15k over the 20k. If YOUR happy with them just keep them until its time to change them out and try something else. I talked to XM and they have a new 15k bulb that they claim has class leading PAR. it should have been out by now (they said first quarter of 2009) but I havent heard anything all year.
Great information, thanks!