Hit the brakes on RTN

kevensquint

Active member
A week ago my new bottlebrush started to RTN, I posted that here for help. My only idea to save it seems to have worked. I switched out my 2 giesemann 13k bulbs for 2 XM 20k bulbs and the flaking and disentigrating frag stabalized, now a week later it is healing and the color is comming back nicely. I think I caught the RTN within hours..or less of when it started, so the quick action prolly helped alot.
 
Me too. I just went from 2X 400W 20K xm's which were overa year old to 2X 400W 15K XM's and I'm losing a beautiful green monti cap. It's RTN'ing all over. It has white patches all over it except for the edges which appear to be still growing. I'm thinking I should put my old bulbs back in to see what happens. The 15K have a lower PAR than the 20K so I don't get why this is happening.
 
kevinsquint,

Most likely you were blasting it with too much light, not enough acclimation. The 20K bulbs have a much lower PAR than the 13K giesmanns. Typically, the higher the K the lower the PAR.

Aquaduck,

I would be very surprised if a 20K bulb had a higher par then a 15K one.. but I don't know that much about XM bulbs, or their quality. Nor do I profess to be an expert on the subject. :)
 
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<a href=showthread.php?s=&postid=6575174#post6575174 target=_blank>Originally posted</a> by Sparkss
kevinsquint,

Most likely you were blasting it with too much light, not enough acclimation. The 20K bulbs have a much lower PAR than the 13K giesmanns. Typically, the higher the K the lower the PAR.
My thoughts exactly. The 13k's were so strong for this particular frag, it went right past the bleaching and straight to the RTNing. Also, don't read into this as bragging or as if I think I'm some kind of coral wizard, just sharing what worked for me, the cause was obvious. Aquaduck XM 20k's do have higher PAR than XM 15k's, just look it up in Sanjays lighting page.
 
Aquaduck XM 20k's do have higher PAR than XM 15k's, just look it up in Sanjays lighting page.


maybe not, after use i wonder where the par is at?
 
Thats what I was mentioning to some of the members of my local reef club and everyone attacked me, saying that there was no way a higher kelvin rating bulb would have more par than a lower kelvin. I looked at sanjay's site as well.
 
is it only these 20K bulbs which have higher par than a lower kelvin rated bulb? i would love to go from 14K to 20K but don't since i'm concerned w/ losing par.
 
For some reason the XM 20K 400W has more PAR than the XM 15K 400W. It's probably due to the huge blue spike in the spectral output. Go figure....

Well the center of my green cap is now totally white. About 3/4" all the way around the edge is still alive. So is it half dead or half alive? :rolleyes:
 
I have had caps come back from center damage like that (one got stung bad once). Here's hoping yours pulls through too :)
 
<a href=showthread.php?s=&postid=6583046#post6583046 target=_blank>Originally posted</a> by kevensquint
Is the tissue gone or bleached on your cap?, I would put it in a shadier area of your tank regardless.

Tissue is gone. I'm going to keep an eye on the edges and if I notice any more tissue recession, I will put some window screening over the tank. The funny thing is the orange monti cap 4" away is doing fine.

I can't move it. It's grown into the rock work. I could snap a frag off of the living side.
 
It may be in a "hot spot". E.Borneman wrote of this before, its when there is a small area more intense light, not necessarily visible to the eye.
 
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