Old growth dying but new growth fine

[Chelsey]

Over the past month or two I've had increasing problems with my blue polyp cap, idaho grape, setosa, superman, and strawberry patch cap. They have all but died except they continue to grow on the edges. It's not RTN because the death of the inner part of the cap doesn't happen quickly. Instead as the coral continues to grow the center slowly starts to die and what used to be "new growth" eventually dies as the coral grows outward. I have several other montiporas in my tank and those are perfectly fine (sanddollar, sunset, undata), as are the other picky sps that I have (oregon tort, icefire echinata, several milles). I do not have monti eating nudis, my bulbs are not old, and I do not have fish munching on the aggravated corals. My values for the last few months are as follows:

2-1-09: Alk 9, Ca 375, Mg 1125
2-14-09: Alk 10, Ca 370, Mg 1170
2-23-09: Alk 9.5, Ca 350, Mg 1125
3-1-09: Alk 12.5 (?!), Ca 400, Mg 1125 -> After noticing my swings I decided to revert back to my original Calcium reactor settings and attempted to redial.
3-4-09: Alk 9.5, Ca 360
3-6-09: Alk 9.5, Ca 375
3-8-09: Alk 9, Ca 400
3-10-09: Alk 8.5, Ca 400
3-12-09: Alk 9.5, Ca 375 (Installed new MH bulbs, Iwasaki 14K)
3-18-09: Alk 9.5, Ca 370, Mg 1125 -> At this point I started adding Magnesium Crystals to attempt to increase the Mg
3-26-09: Alk 9.5, Ca 425, Mg 1125
3-28-09: Alk 10.5, Ca 375, Mg 1135
3-30-09: Alk 8.75, Ca 375, Mg 1125
4-8-09: Alk 8.5, Ca 400, Mg 1250
4-18-09: Alk 8.5, Ca not tested, Mg 1200

This past week has been hectic and I did not notice until a few days ago that my effluent line was clogged...bad thing.

4-24-09: Alk <7, Ca 375, Mg 1100 -> effluent line cleaned and reset to 30 mL/min

4-25-09: Alk 8.25, Ca 375, Mg 1150

If you are so inclined you can read my thread that I started in my local forum here (http://reefcentral.com/forums/showthread.php?s=&threadid=1588518). My Calcium reactor is a Geo 612 and now that I have it dialed in and situated it holds the Alk and Ca relatively steady (provided the effluent line doesn't clog). I have been slowly working on getting the Ca up to 450 by adding Kent Turbo Calcium and the Mg up to ~1200 via Seachem Magnesium crystals but I do not add both at the same time.

I would greatly appreciate any help or suggestions that you can give. I realize that my levels have fluctuated but it doesn't make sense to me that only a few corals would be affected and the rest would be fine. Thanks in advance!


Chelsey

[Chelsey]

^^^

[jakester]

I would first make sure you have good flow around the coral(s) that you are having problems with.From my experience Caps and monti need at least good enough flow to keep detritus from sitting on them. The other thing I would do is raise you Mag. up to at least 1280-1350. I think most would agree on this one. Also a lot of caps and monti don't do as well in higher light and sometimes it can take 2 weeks to a month before they start to have a negative effect from a brand new bulb if it is putting out a higher level of par and the corals are not acclimated properly. Hope this helps. These are the first things I would look into from my personal experience.

[Nanook]

I would get your calcium up to 450-ish and magnesium to 1300-1400-ish.

What is your temperature range?

What is your specific gravity? How do you keep it stable?

What is your nitrate level on a quality nitrate test kit that checks low range?

What is your phosphate level " " " " " " " "??

What is your tank ph during the day and during the night?

[t4zalews]

definitely keep your Ca level above 380, as above the ideal is 420-450.

[jakester]

Well put Nanook! My response was in assumption that all the other water parameters were in check. And you know what happens when you make an assumption in this hobby. :eek1:

[Dejavu]

Have you calibrated your refractometer if your using one? IME low Mg seem to effect monti's first.

[Chelsey]

I'm working on getting Ca and Mg up but I don't want to do it all overnight. How fast do you think I can safely bring it up?

Refractometer gets calibrated every time I use it.

Temp range: 78-81, usually on the lower end of the spectrum

Specific gravity: 1.025 -> I keep this stable via ATO and make sure the water change water is the same SG

Nitrate level is 0

Phosphate level I'm not sure about, I've never tested it, but I will say that I have no algae to speak of.

tank pH I'm also unsure of but I can check. The last time I checked it was ~8.3 during the day time.

I just adjusted some of my Tunzes to increase the flow to the remnants of my problem corals. I've noticed that my sanddollar has not had good polyp extension for the last 4 days or so but I'm attributing that to me sending the Tunze that was providing flow to it off to get fixed. Tunze came back good as new today :)

I greatly appreciate the help everybody :) Let me know how fast I can bring up my Ca and Mg and I'll get it done ASAP. Thanks again!


Chelsey

[Nanook]

I wouldn't raise calcium more than 20-30ppm/day and magnesium more than 100 per day. I would be curious to see what your phosphate and nitrate levels are with quality low range kits.

Do you have sand in the tank? If so, it might be time to gravel vacuum it out to get rid of excess detritus.

How many Tunze pumps are you using? I think it is possible to have too much flow.

[jakester]

I agree with that statement!:)