Large Birds nest colony RTN

[Flippers4pups]

Rtn is started by a stress event. Water parameter swing or parameter consistently incorrect, temperature swing, excessive par, etc....

When this happens, bad bacteria attack the compromised tissue and kill it. This allows the proliferation of the bad bacteria which can allow their numbers to then spread to healthy coral nearby. This is why RTN can spread to healthy corals nearby. Pathogens then eat the dead or dieing tissue, exposing the skeleton underneath. This is a very watered down explanation of a very complicated process.

 

[Charlie’s Frags]

Still looks like salt burn to me. Ernie did you pour your new water right over this piece?

 

[Ernie C]

No. I usually slowly pump new water into sump. My alk was stable. I dose kalk Hourly as top off and two Part three times a day. Alk is steady at around 7.8

I think it was a combination of stressors. My temp has tended to be on the higher side but the last week or so due to cooler weather my AC would kick off less and the temp was peaking at 80.

I clipped the tips and made frags. Dipped them in melafix and they seem to be ok. I had a chiller I had not installed and so got that online. one tiny 1/4” frag also seemed to have started to loose tissue so I tossed it.

so far haven’t noticed anything else. I Put some carbon in the tank and poly filter just in case. Keeping an eye on the frags but no signs of RTN as I would have noticed of how fast it goes. Fingers crossed.

 

[Ernie C]

I had older frags of it on the sides of the tank that had a darker green. This colony was directly under one of the hydras. So I’m thinking maybe a combination of too
Much light, restricted flow since it had gotten very dense, higher temp, etc. I’m not familiar with salt burn but I don’t dose anything into the tank. It all goes into the sump. Also it went up like a match in 48 hours which sounds more like RTN. First time I e experienced this so it was pretty scary. Hope nothing else goes the same route.

 

[Charlie’s Frags]

Salt burn is what happens if you pour a poorly mixed batch of water on a coral and salt particles touch the coral

 

[Flippers4pups]

Salt burn is what happens if you pour a poorly mixed batch of water on a coral and salt particles touch the coral

I believe your referring to osmotic shock. Salinity difference from the surrounding water column. This would surely cause some damage, but most likely the whole coral would be effected if blasted with a stream of it directly.

 

[Charlie’s Frags]

I believe your referring to osmotic shock. Salinity difference from the surrounding water column. This would surely cause some damage, but most likely the whole coral would be effected if blasted with a stream of it directly.

I’m talking about when un dissolved salt hits coral tissue. It will burn just the affected areas, but it sound like this is not the case.

 

[ruskimax]

I’m talking about when un dissolved salt hits coral tissue. It will burn just the affected areas, but it sound like this is not the case.

Yes, dissolving salt in water causing an exothermic reaction which would cause direct tissue necrosis. No idea the chemical mayhem that would cause added to the heat released from dissolution.