Montipora losing its tips, need some advice

[changm]

So I bought a small stand of green monti digis, understanding that this is a good beginner's coral.

I placed it near the top of the tank, and watched it grow. After 4 weeks, I saw that it has grown new tips at the edges. Very happy.

Then over the last 2 weeks, I noticed that the new tips are disappearing. Upon closer observation, I notice that the the places that have lost tips are white and in some cases, it looks almost as if a whole bit has been lost. I cannot tell if it just dissolved, or if it was "chomped" off. The rest of the colony seems normal, PE is evident. Colour is not popping green but flourscent under blue light. No sign of RTN.

Some basic info:

* 24G modded nanocube, running about 3 years now
* KR91 LED lighting
* pH 8.1 to 8.3
* Temps - 79.5, +/-0.2
* Ca ~440
* Mg ~1800
* Flow - just the main return pump, a maxijet (can't remember model, its the mid range one)
* Other corals: Mostly easy LPS and softies (torch, frogspawn, gsp, tree)
* Fish: Small clown, yellow-tail damsel, royal gamma
* Water changes: 20% every week
* Skimmer - yes I skim, euro-reef nano, half a cup of dark gunk every week
* Refugium - whole of chamber one full of chaeto and pods, on reverse lighting cycle
* phosphates - I don't test for it but I run a GFO reactor in the back
* Inverts: couple emeralds, several cowries, a turbo, an astrea



By all accounts everything else is doing fine. Water quality should be fine. I don't have algae problems and coraline is growing. A couple spots of red slime which I siphon off every week.

So, what can be the cause of the disappearing growth tips?

* Water quality? something wrong with my water chemistry?
* Flow? Not enough? the spot that the monti sits on is relatively low flow
* Lighting? Too little? Too much? Hard to imagine it is insufficient, but I don't know.
* Getting Eaten? Predators? There is a commensual crab that lives in it. Hairy. I researched and believe it is benign.
* Chemical warfare? Is the leather poisoning it?
* Alkalinity? I do not test for this, could it be an issue?
* Other thoughts?



I would really appreciate any suggestions. I am hoping that I can determine what is causing the problem. Maybe this tank just cannot keep SPS?

 

[Atomikk]

Montipora eating nudis.

Do a search here, as I am sure it has been covered to death.

 

[changm]

Thanks for the quick reply, I'll look into it.

 

[changm]

Pics

Pics

So, here are the pics before and after. You can see the tips near the upper right side show some noticeable loss. Nudis?

Greatly appreciate your insight!

 

[fishboarder]

i think it might be high alk.

 

[changm]

i think it might be high alk.

What can I do about this? I think I know how to dose up my alk, but how do I reduce it?

 

[ingtar_shinowa]

i havent seen numbers for alk, am i blind? Also why is your Mg so high?

 

[changm]

i havent seen numbers for alk, am i blind? Also why is your Mg so high?

I don't test for Alk (but will do so now just to see what it is). Mg so high? No idea.

I do 25% water changes weekly in hopes that this will replenish my elements - is this a faulty line of thought?

Appreciate your thoughts.

 

[ingtar_shinowa]

no you are right about this, but depending on what you put in your tanks yourcorals can soak up alot more than weekly water chagnes can replace. And i have never heard of a salt mix with 1800 Mg lol. That is pretty high.

 

[changm]

no you are right about this, but depending on what you put in your tanks yourcorals can soak up alot more than weekly water chagnes can replace. And i have never heard of a salt mix with 1800 Mg lol. That is pretty high.

I'll look into it. Probably got the Mg reading wrong. Thanks so much!

 

[maysorum]

IMO, alkalinity is very important element to test. I bet your alkalinity is way off and should be in between 7-11 DKH.

 

[losthere]

IMO, alkalinity is very important element to test. I bet your alkalinity is way off and should be in between 7-11 DKH.

+1

Alk is just as important as anything you test for. (Probably one of the most important)

I have had a timer malfunction and dump a whole bottle of B-Ionic calcium in my tank with no problems. If that would have happened to the alk, everything would have died. Alk swings are more way devastating than cal swings. Testing your alk is one of the basic fundamentals of reefkeeping.

You mag is very high so I would guess that your alk is off as well.

Good luck.

 

[changm]

So I tested my alk and it shows 2.0 meq, it's too low from what I understand.

My question is what may be the cause? What should I watch for?

I am now using Seachem Reef Builder to try to dose back up the Alk, any suggestions on what to watch for?

 

[jackinfobo]

I can't believe how low your alk is! This is deffinatly what your problem is. Just like with any any element, they all get depleated after a while which is why you must dose for Ca and such. Alk is no different and if you don't dose it, it gets depleated. I would just say to slowly raise the Alk so you don't shock anything. Once your Alk is in the correct range then other elements like your Mg should follow and everything will become more stable. Depending on what you have in your tank I would keep the Alk between 9 and 12DKH

 

[changm]

I can't believe how low your alk is! This is deffinatly what your problem is. Just like with any any element, they all get depleated after a while which is why you must dose for Ca and such. Alk is no different and if you don't dose it, it gets depleated. I would just say to slowly raise the Alk so you don't shock anything. Once your Alk is in the correct range then other elements like your Mg should follow and everything will become more stable. Depending on what you have in your tank I would keep the Alk between 9 and 12DKH

thanks for the insights, I guess my alk just got depleted over time.

I am still a bit puzzled as I do 25% water changes weekly, I thought that would be enough but I guess not!