RTN at the base

[haze152]

So over the last 3 days I had an Alk spike from 7.8 to 12 back to 8 in 48 hrs is that enough of a swing to cause RTN? Is all I can do at this point is cut small frags and toss the colony? What else could have caused the RTN?

[victoly]

Nothing else caused it. A swing of 4 is almost assuredly the cause. Sometimes you can mitigate the damage by fragging the tips, like you said.

[haze152]

That's what I was afraid of. Just hoping the tank does not crash at this point. So far only 3 acros have RTNed.

[Juiceman]

That much of a swing can definitely do it. Dip and or Frag is about all you can do to save everything.

[haze152]

Last question I order some SPS that will be here tomorrow and I do t have a QT planing on building with my new tank. Will the new frags be okay since they where not in the tank during swing?

[ckyuv]

You should be fine if the swing is what caused it

[+etannert]

I would do carbon and a water change before adding the new colonies. I've seen and heard that the old skin sloughing off can trigger a new RTN event on a previously healthy colony and that dying colonies can let off a chemical that tells other corals to "jump ship."

[haze152]

Good news and news. The RTNing has stopped good news. Bad news I lost about 60-70% of my colones. The new corals from aqua SD have been In the tank for 5 days with no RTNing.