Acro tissue loss... maybe high Mg

[deftonead]

Hi,

I'm having an issue with losing tissue in between the branches at the base of all my acro colonies. Close to 50 different colonies... I've been dealing with this issue for close to 3 months now and i cannot figure it out.

Corals are still growing good and have good color but dead spots...

Tank is going on 3 years old.

Alk 10dkh
Ph 8.3
Ca 480
P 7ppb
NO3 2.5 ppm
Mg 1500+ ppm

Fish:
sailfin tang
3 anthias
sixline wrasse
cardinal
mandarin

At first I was thinking parasites but i have cut and dipped multiple multiple branches and have seen nothing.... not to mention everything new is quarantined for at least a month before it goes into the tank. I dip and inspect every frag once a week during this period. Plus not seeing any bite marks or eggs anywhere.

One of the first things i did was up the amount of flow. i have added a ton more so there are no dead spots. I mean the flow is cranking in there and I see no difference! Im too the point where I think it may be too much and i may back down a little.

Im leaning toward maybe Mg because it is off the charts high and im not sure how it got this way considering i dont add any and my water change water has been testing at 1350 ppm consistently. Ive used several different kits and come up with the same numbers.

i use a brs rodi 7 stage and change my carbon filters religiously every 3 months and my tds is always 0. I have recalibrated the tds to be certain. dont think Mg is getting in that way...

Anyone ever see this issue with high Mg?

Im working right now and will try to post some pics later.

 

[andrewey]

Have you considered your nutrient level in light of your alkalinity? The phorphorous checker has an accuracy of +/- 5ppb (+5%), so at low levels such as 7ppb, you're looking at an accuracy window of 2 to 10 ppb (so it's possible you have 0.006ppm phosphate in your water column).

My first thought would still be to rule out any pests munching on the acros, but I might keep the nutrient levels in relation to alkalinity on the differential.

 

[Laurens]

How big is your tank? Have you had fish losses? Any alk swings? What light, and any changes in light? Seems like you have little fish for 50 acro colonys.

 

[Graffiti Spot]

Let’s see some pics. As long as mag is raised and lowered slowly it won’t hurt anything. I am not sure what a spike in mag would do exactly but maybe someone has experience with that.

 

[jda]

People used to (and still do) go way higher than this to kill bryopsis with magnesium supplement. I would be skeptical that it is magnesium.

Those numbers all look OK... nothing growth limiting. Recalibrate your refractometer and double check your temperature using something with mercury in it.

After this, I would lean lighting... acropora STN from the base with too little lighting or low spread.

 

[Graffiti Spot]

You can refill the dropper and keep dropping them til it changes color with the salifert kit. Just add past 1500 whatever each ml is equal too until it changes. But yea I was at 1700 when I used tech m to kill off bryopsis.

 

[Backreefing]

People used to (and still do) go way higher than this to kill bryopsis with magnesium supplement. I would be skeptical that it is magnesium.

Those numbers all look OK... nothing growth limiting. Recalibrate your refractometer and double check your temperature using something with mercury in it.

After this, I would lean lighting... acropora STN from the base with too little lighting or low spread.

Hi I’m currently haveing similar issues with my 90 . Unmeasurable high mag . Resending at the base of a few corals . But I have Dino’s as well . And zero algae.

 

[TX_Punisher]

Hi I’m currently haveing similar issues with my 90 . Unmeasurable high mag . Resending at the base of a few corals . But I have Dino’s as well . And zero algae.

whats your no3 and po4?