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View Full Version : favia and acan now showing tissue loss


jlinzmaier
10/18/2009, 05:40 PM
Hello.

I have a 180 gallon tank. Well maintained, regular water changes, water params kept in check and steady (two part dosing). MH 400 watt lighting (radium 20K). Lot's of flow.

About a month and a half ago I stopped using my ca reactor and switched to kalk dosing for a higher pH value. After about 2-3 weeks of alk fluctuations with the kalk dosing I started using a two part solution with dosers. During the alk fluctuations the SPS showed a bit of stress and polyp retraction but everything else looked good. In addition to switching to two part dosing I also decided to raise my alk level slowly to see how the corals responded. I was using the zeo method a while back and kept my alk around 7.0 dkh (per zeo guidelines). Since I'm not using the zeo method anymore (stopped carbon dosing well over 4 months ago) and I don't believe I'm at an extremely low nutrient level, I decided to slowly raise the alk level over a few weeks to see if a higher alk level would yeild faster growth rates. Once I got to 8.5-9.0 I kept it there for a week and I started to see new growth tips. With the increased growth after upping the alk I decided to continue to up the alk and see what happened. At around 10.0 I started to see some stress in the SPS and a lack of polyp ext. I then decided to lower the alk back down to around 9.0. At the time I lowered it back down to 9.0 I started to see some tissue loss in my prizm favia. I thought is was stress from the recent alk changes so I gave it a bit of time to recover. After a week it still wasn't doing better so I did a 5min dip in revive solution. It's continuing to loose tissue and looking like the entire colony will be a loss.

I was going to chalk it up as a lesson learned and live with the fact that my attmept at increasing alk rates to increase growth rates was too stressful an event for the favia. However, now I'm seeing some tisse loss in one of my acan colonies in similar fashion of how the favia started.

My guess is that I'm still at quite a low nutrient level and my alk level of 9.0 is still just too high. I'll slowly back it down to 8.0 and see what happens. I know there are many occurences of tissue necrosis in SPS when there is ultra low nutrient conditions in conjuction to alk levels higher than 8.0 but I wouldn't think my LPS would be more sensitive to that then my SPS. At this point the SPS look pretty good and don't seem stressed.

Any suggestions to my quandry other than tying to lower my alk level down to 8.0 and see how they respond??? Please keep in mind that as I was making alk adjustments I did it very slowly by changing the rates of my doser and never did I make changes of more than 0.5 dkh in a 24 hr period.

Any thoughts or input would be greatly appreciated!!

Jeremy

PCfishman
10/18/2009, 07:08 PM
Alk is certainly one parameter to pay attention to but, CA, Salinity, Temp all play a part in coral health. Have you tested those, if so what are your readings on those elements?

jlinzmaier
10/18/2009, 07:43 PM
Alk is certainly one parameter to pay attention to but, CA, Salinity, Temp all play a part in coral health. Have you tested those, if so what are your readings on those elements?

Won't go into details but everything is right on. No major fluctuations and everything is just right. Alk is the only thing that has changed recently.

Jeremy

roblack
10/19/2009, 11:28 AM
Alk of 9.0 is not too high, in fact it is good, could go higher and be fine. Fluctuations can cause stress/loss. Check your mag, gets depleted sometimes, especially when the alk and ca have been played with. Mag should be high for most lps, over 1250 for sure, some say over 1450.

jlinzmaier
10/19/2009, 01:03 PM
Alk of 9.0 is not too high, in fact it is good, could go higher and be fine. Fluctuations can cause stress/loss. Check your mag, gets depleted sometimes, especially when the alk and ca have been played with. Mag should be high for most lps, over 1250 for sure, some say over 1450.

Mag is fine at 1450 per ELOS kit.

In an ultra low nutrient system an alk of 9.0 is not OK and will cause RTN on stony corals. In an ultra low nutrient system the alk must be kept at NSW levels which is around 7.0. I believe that's why my corals showed so much stress as I increased the alk. If I bumped the alk up to 10 now I'm sure I'd have more tissue loss on several other corals. I agree that in a common tank an alk lvl of 10 is fine, but not in an ULNS. I think because of good husbandry and recently being at an ultra low nutrient level from the zeo process I'm still seeing some coral stress R/T the alk increase.

That's my guess anyway. I was just wondering if you LPS experts had any other ideas or suggestions for trying to save these stressed LPS.

Jeremy