Something is breaking my life rock

[Happyschneider]

Hi all,

My tank is up and running since last July. Despite some algae growth, my water values are stable. Only ALK had a dive as the dosing line was clogged and I only found out the other day.

ALK is measured with Hanna and is not dKH but ppm!
Obviously Magnesium is high as well. There was a dosing mistake and I intend to let it run down by itself.
Salinity is at a constant 35 ppt (refractometer).
Nitrate and Phosphate measured with Salifert and Milwaukee (like Hanna), respectively.

I have a few corals, more hair algae that I care for (algae scrubber planned and currently running GFO), some red bubble algae (need to get this out of the system asap). In terms of mobile inhabitants I have some snails (turbo and nassarius), pair of cleaner shrimps, 2 assessor flavissimus, 1 Cryptocentrus cynctus, 2 Chrysiptera parasema

Together with the yellow prawn goby, I got an alpheus lullubus which I suspect to be the culprit. However, I added it already in November and I did not observe anything until now. In recent weeks, I observed that small parts of the life rock gets broken off. First I thought nothing of it as I might very well have knocked it off myself, I do tend to be a little bit clumsy. However, yesterday I saw a clean break of a bigger part underneath a rock arch, where I do never go myself (can't really reach).

So I have two questions:

• Should I worry about my rocks beeing broken?
• Could it be the pistol shrimp?

I never have observed any of my animals doing anything, and I would not remove the pistol shrimp (not that I have seen or heard him since December). I just wonder if I should expect all my reef build being transformed into rubble or if there is anything I could do to prevent it (offering more rubble in the tank for the lullubs to build with)? Any input is highly welcome!

 

[Bent]

I don't think pistols are in the habit of breaking rocks. Sounds like a mantis to me. Could be a bobbit, but a mantis is more likely.

 

[Happyschneider]

:uhoh3: Oh please do not let it be a bobbit worm! Not going to touch my aquarium anymore :facepalm:

Mantis would surprise me. How small can they be?

In any case, both options would probably be the end of my fish, I guess. At least once they get bigger...

 

[Justdrew]

95 ppm is only 5.32 dKh. Way too low. Probably not causing any rock breaking but will cause other problems.

 

[Happyschneider]

95 ppm is only 5.32 dKh. Way too low. Probably not causing any rock breaking but will cause other problems.

Absolutely! I normally try to keep it around 150 ppm. I dose 15 ml per day on a 180 liter (about 40 gallon I think) tank. It dropped within 2 weeks to 95 as I was not testing ALK during that time (holidays and bad cold). So now I am slowly bringing it back up again.

You think it could lead to decalcification of the stone and this could lead to the breaks? Euphyllias look good, they are still open and seem to be growing (I can see new heads).

 

[Bent]

Mantis can be pretty small and still bust some live rock up. It doesn't take much to break it.

Go hunting at night with a red light. (I use my phone).

I turn the brightness on my phone all the way up, google image search "red", and make the image full screen. Then use that light to look.

You'll catch it in the act. It's def an animal.

 

[CStrickland]

Is it Caribsea brand "life rock"?
If so I remember a thread where some folks had trouble with it flaking and crumbling in spots. I can't find it now, and I don't remember whether it was a bad batch or something with their water chem. Was your ph affected by the alk dive? I wonder if that might weaken the structure of the rock to enough that weaker bits could break off. Maybe if you can find the thread there will be something there that helps you

+1 on the red light night hunting. That's good times

 

[Happyschneider]

Mantis can be pretty small and still bust some live rock up. It doesn't take much to break it.

Go hunting at night with a red light. (I use my phone).

I turn the brightness on my phone all the way up, google image search "red", and make the image full screen. Then use that light to look.

You'll catch it in the act. It's def an animal.

Ok, I know what I will be doing during my insomnia spells in the next few nights Thanks for the tip with the red light on the cell phone. What did we do before we had those fantastic little helpers?

 

[Sk8r]

Gloves and ordinary kitchen tongs are useful when hunting the untouchable.

 

[Happyschneider]

I have gloves, tongues I have from my fresh water scaping days. If I don't get back, inform the men in black