Stn?

[CastAway]

My tank has been running almost six months now, my first. In those six months I’ve had two really discouraging events. First, I lost three fish - I have no idea why or how. That happened in July. And now, it appears as if I’m going to lose some SPS.

I only have four pieces of SPS in my tank. The first was a green monti-cap, my very first piece, added Apr 18^th, which appears to be doing great. It had a bout where it lost its color, when I first started my GFO, but is has more than quadrupled in size and is a vibrant green at this point, trimmed in new white skeletal growth.

The other three pieces of SPS are all birds nests, one sour apple (pictured), a pink birds nest and a hyacinth which was gifted from Todd (TJ’s Reef).

All three bird’s nests seem to be doing the same thing, they were growing gang busters, then stopped, and are now sloughing off tissue. As a newbie, I have no real idea what constitutes “rapid†from “slowâ€, but it has been two weeks now watching them diminish. As best I can tell, my params are all good.

I did begin adjusting my Ca reactor a couple weeks ago, trying to get my dKH, Ca & Mg to more desirable levels. Alk went from 10 to 13 over the course of about a week and a half, Ca from 400 to 430, and Mg from 1260 to 1340. If there was anything that I can tie the TN to, it’s this. But, it was over a span of time, testing twice daily making minute adjustments to CO2 and reactor effluent output, and the new values are closer to target. To get Mg up, and not drive Alk too high, I did use SeaChem’s Ions product.

So what’s going on? Too much change in too short a time? STN that I can do nothing about? Please help.

 

[ReeferBee]

I've found that birdsnest are the first to STN from the base up, if there is an alkalinity swing. I consider mine to be the "canary" coral of my tank.

 

[CastAway]

I forgot the picture. Not really TN at the base, or tips, but just on the stem.

 

[ReeferBee]

That is odd, maybe the high alk irritated them? I've never looked into the effects of high alkalinity, just a guess..

 

[CastAway]

I think so. But if the only way to get my Ca and Mg up to also ends up driving my dKH too high, then what the heck do I do? Why even have a Ca reactor? So so frustrating.

 

[ReeferBee]

Dose just calcium and mag until you get them where you want. I'm sure you know this but calcium reactors are designed to only maintain levels. by dosing calcium you alk level will come down too. At that point dial in the calcium reactor to keep the desired levels stable.

 

[CastAway]

I really thought a Ca reactor was supposed to eliminate the need to dose in general. Would not be my first completely wrong assumption. Perhaps a water change is in order to bring the dKH down.

 

[deboy69]

As stated above they only maintain your levels. You must first dose your system to where you want them and then dial in your reactor to maintain them. Dont try to raise your levels with your reactor you'll do more harm then good.

 

[CastAway]

As stated above they only maintain your levels. You must first dose your system to where you want them and then dial in your reactor to maintain them. Dont try to raise your levels with your reactor you'll do more harm then good.

Then this is exactly what I've done - i.e. harm. What's still confusing is, what do I dose, and what do I rely upon the reactor to provide? My guess is to dose Ca and Mg, and set the reactor to keep dKH where I want it, maybe 10, or lower. I can tell you right now though, barely any effluent will be coming out of the reactor doing this.

 

[msderganc]

Just an aside...take a look at Randy Holmes-Farley's papers on chemistry. Raising your levels far above NSW is probably not that helpful. The key is just balancing the three and holding them constant. Alkalinity is by far the most difficult to maintain, and the hardest on corals when it swings.

 

[msderganc]

Then this is exactly what I've done - i.e. harm. What's still confusing is, what do I dose, and what do I rely upon the reactor to provide? My guess is to dose Ca and Mg, and set the reactor to keep dKH where I want it, maybe 10, or lower. I can tell you right now though, barely any effluent will be coming out of the reactor doing this.

What he means is to dose your tank to the desired levels (one time) then use the reactor to maintain those levels. It will put out calcium and alkalinity (and magnesium with the right media) in the right balance to consumption by corals. Occasionally you may need to dose to bring the elements back in line if, for instance, there is a bacterial bloom which consumes a lot of the alkalinity but no calcium.