So, as the discussion goes, is it actual nutrient levels that are important or is it stability that is important? Probably both.. However, some people would argue that when transferring drags from one system to another, with dramatically different parameters, the corals acclimate perfectly.
... I don't really know where I'm going with this, I guess, other than to question why in '07 your system exploded with growth and today, it is struggling..
Tell me if I'm off base here and you are pretty sure the acro explosion is just around the corner and you aren't questioning all of this yourself..
If that's the case, sorry for the sidetrack!
Even though I might not have posted about it I have always tested my nutrients and tracked them in a log book. Ironically just last week I was going through both pictures and logs to see what was different with my tank back then that I am struggling with SPS now, more of that in a second.
Back in 07-10 when I had the tank running as good as I could have hoped I was very aggressively running GFO and carbon dosing vodka. At one time I had chaeto in one of the sumps but it never really took off so I ended up removing it. Now I know that the chaeto was not doing well because the carbon dosing was pulling the nutrients out that the macro algae needed to grow. If you are carbon dosing you shouldn't be using macro algae for nutrient export.
But last week I went through my notes from when this same tank had lots of corals that were all thriving. I looked at the parameters of my tank back in 2010. The tank was stocked to the brim with macros and the growth was very strong. I went from a tank of nothing but small 1" frags to full blown colonies in about 18 months. My alk, at the 10-18 month mark, was all over the place from 11 dkh to as low as 6.6 dkH, with fluctuations of about 1 dkH every time I took my readings. N was always less than 0.1 and P was between 0.02-0.01. Despite the fluctuations in alk, I had zero problems with my SPS growth and coloration.
So I still think, as I did back then, that stability is really the key and that with either low Nitrates or high Nitrates you can be successful. With the method I am using right now, back to basics, I am really trying to achieve a less active means of keeping the tank running. When I was carbon dosing and using GFO, the carbon dosing was easy, just set the dosing pump up and let it go, Nitrates gone. But I was using GFO to pull the P down and it was erratic at best as I would forget to change it all the time, and while it did not cause bleaching it still allowed my P levels to bounce around a little. I say a little because it would go from about 0.08 to 0.02 still nothing major. Right now I am doing Nitrates with the thought that I will add more fish and feed more and eventually not dose nitrates.
But back to my problems right now with SPS. All my other LPS and fish and even the tank itself (rocks and coralline growth) have been spectacular the last 3 months. SPS has been really disheartening. I have only been using frags, but they would go into the tank look initially good, keep their color and encrust, but then they would just brown out, tips burn and eventually go dormant and either stay that way or RTN one day. I have no idea why this was happening, I have been testing and calibrating everything at an obsessive level the last few months. Everything is perfect, my alk has been rock steady for about two months, but still I was having problems, they were now taking a little longer to manifest, but still the same pattern.
So approximately one month ago I did two things, I re calibrated my refractometer using to two separate calibration fluids (Randy's homemade and Pinpoint), before that I had using the refractometer calibrated with RO/DI as per the manufactures guidelines (I know should be using 35ppt fluid). Using the calibration fluid I was off about 3ppt and raised my salinity over the next week. But more importantly I switched salt again, this time I went back to IO. I did about 200 gallons of water changes over the weekend and two more the next week, then went back to water changes every other week. I have been actively observing the SPS that were in the system and am positive that I am seeing better coloration and actually growth. A few new axial corallites can be seen on a few frags and no tip burning on any of them. Right now I am very hopeful that it was the salt that was causing me problems. If things continue as they are for the next few weeks I think I may have turned a corner.
Circiling back to when I was looking at my notes 2010 I was also looking at pictures and found that back in 2003 I had a bunch of acros with tips that were burned. This was from when Ron Shimek put out his article on the toxicity of some freshly mixed artificial sea water. I, after having read that article, changed my salt to Marinemix Bioassay from IO. Within a few weeks the tips of my acros started to melt away and I had some colonies RTN on me. I ended up switching back to IO and it went away. I went back to read the history from RC when this went down and it sounds very familiar to my current problem as well as the acro tip burning that so many people keeping SPS are having now.
<a href="http://archive.reefcentral.com/forums/showthread.php?s=&postid=1436691#post1436691" target="_blank">http://archive.reefcentral.com/forums/showthread.php?s=&postid=1436691#post1436691</a>
<a href="http://archive.reefcentral.com/forums/showthread.php?s=&postid=1429957#post1429957" target="_blank">http://archive.reefcentral.com/forums/showthread.php?s=&postid=1429957#post1429957</a>
I have my fingers crossed that this fixes my problem.
Ha! I think I am the one who is rambling now!
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