Some SPS RTN issues

Sorry to hear that!  But I know how you feel Bill!  I had a couple of my acros that I bought recently RTN on me as well.    I see a few parameters that are off.  Your Ca is high at 500.  You want to keep it around 400-420.  But I think over time that will get fixed by you keeping your alk high.  I heard that Oceanic does have higher Ca so that might be the source.  Your PO4 is a little high as well you want to be as close to 0 as possible.  PO4 will prevent acros from growing.  Your Mg is also high.  you want to be in the 1300-1320 range.  I think the Mg might be the reason why your acros are RTNing.   maybe it's all those parameters that is the cause?  I've had my Ca, Alk, and PO4 a little on the high side in the past and did not see any adverse effects.  How often do you do water changes?  How do you acclimate your new acros?  Do you have a Phosban Reactor?  If you don't have one of those, I think it's a must have for people that keep SPSs.  It does wonders with PO4 and it can also be used with other media as well (Nitrate sponge, carbon).                            

Have you tested the parameters of your "water change" water?  That might be the cause of the high parameters.  If it is, you could try a different salt.  But if the parameters are within the correct range then you could start doing a 20g water change once a week.  That might help bring some of those parameters down. 

ct79 wrote: Have you tested the parameters of your "water change" water?  That might be the cause of the high parameters.  If it is, you could try a different salt.  But if the parameters are within the correct range then you could start doing a 20g water change once a week.  That might help bring some of those parameters down.

Yes, I'm going to start with IO.  Then I'll probably do a mixture of IO and Oceanic.  I'm also concerned with my salinity being accurate.  Thanks for your advice.

Steve, thanks for the offer...if I cannot find anyone closer, I'll take you up on that for sure!

Mike what does your Saturday schedule look like?

Thanks Mike...I'll hook up with you tomorrow.

Mark Peterson wrote: Do you have good coralline agae growth in this tank? Have you noticed any patches of Coralline turning white?   When too much Ca is being added by too frequent and too large of water changes with Oceanic salt, adding Alkalinity to artificially keep dKH at 11 messes up the water chemistry.   I'd simply stop all water changes, watching the Alk and Ca, then adding one or both components as needed. SPS will grow just fine, even if alk is at 8 dKH. And Ca can be as low as 350 for short periods of time, but it's allowing the tank to find it's own balance that makes the difference.   And whatever you have done to bring Mg up that high - stop it.   When you resume water changes, to use up the Oceanic, mix IO and Oceanic salts.   Also, I doubt it's a salinity issue, but it's good to calibrate the hydrometer. After that, keeping the Hydrometer clean by a freshwater or RO water rinse after each use will keep it accurate. If it becomes cloudy a vinegar soak will clean it just fine.   Do you have any reason to adjust the O3? Can you tell us more about how the O3 and controller have been behaving?

Thanks for the reply Mark.  As far as coralline algea, yes it is going well. I do have a largespine urchin that munches it up rather quickly, so it is hard to tell, but I do think there are some patches that are getting a little white.

As far as what has caused the he Ca and Mg...the ONLY thing I did was do some large water changes with Oceanic.  I have to assume that my hydrometer is way off and that must have caused this issue.  My reasoning is that if my salinity was way higher than I expected it would cause extremely elevated Ca and Mg levels with Oceanic, do you agree?  I'm going to Mike's house today to get it calibrated and then I think I'll be purchasing a refractometer.

With your advice, I'll stop doing water changes.  You say to not artificially keep my dKH at 11, so if I'm reading your advice correctly I should allow it to drop to 8 before dosing?  I'm certainly not questioning you but, I was under the impression that if you raised your dKH it would lower the Ca.

As far is the O3, I'm not too sure I understand the question.  I personally do not have any reason to adjust the O3, or do I?   The ORP probe is hooked up to my Aquacontroller and seems to be doing well.  I have noticed that the ORP is much higher at night, which I cannot remember if that is normal or not but in the last day I'll tell you what it was:

Highest point was 379 @ 6:30 am (this morning) and the lowest point was 361 at 1:30 pm yesterday.

Thanks again for chiming in and please share any additional insight you have.

Hey Mike or anyone else with salinity experience...I'm going to lower my salinity...how fast is too fast.

Cool Mike thanks for the link!

Salinity is not solely responsible for the problem. 1.030 is not that bad when you consider the WMAS recommended range is 1.022 - 1.026. Water chemistry readings will not be significantly different. The change in salinity is only 0.5% and that's all the change you will see in chemistry readings.

Edited by Mark Peterson - June 16 2007 at 5:44pm