20k growth

[Chuck239]

There have been some recent posts about k rating. I've read some different things about the low par rating of 20k lamps and low growth rates. Then one article claimed blue light grows sps better than white and 20k's had the best growth rate.
I wanted to switch out my 14k 250w lamp for a 20k but I'm nervous about reducing my par rating by half and stopping all growth.
I was looking for input from people running 20k lamps and what kind of growth they see?
Would supplemental feeding help offset the loss of par and keep my coral growing?

 

[kevinpratt823]

There have been some recent posts about k rating. I've read some different things about the low par rating of 20k lamps and low growth rates. Then one article claimed blue light grows sps better than white and 20k's had the best growth rate.
I wanted to switch out my 14k 250w lamp for a 20k but I'm nervous about reducing my par rating by half and stopping all growth.
I was looking for input from people running 20k lamps and what kind of growth they see?
Would supplemental feeding help offset the loss of par and keep my coral growing?

Different brands of 20k have very different par ratings. I'm pretty sure the best par/color combo is with Radiums, and growth is respectable. Some 14k like Ushio, look very yellow/white at best, where a pheonix 14k looks nice and blue. The Radium 20k looks very similar in color appearance to a Pheonix 14k, these are my 2 choices. I have also had a coralife 10k that had more blue/white than the ushio 14k.