What is ticking off my sps?

[Baronen]

I have some basic sps (green acro, purple stylo and a starlet coral that came on my rock) it was all doing great until I added a tailspot blenny and some other coral from an lfs

parameters are pretty stable

salinity -1.25
Phos - like .05 to zero
Nitrate - 0
Alk - 7
Calcium - 380

they were all super puffy before the new additions. First time with sps so I am wondering if this is what a fish picking at corals would look like

 

[ZoixDark]

Bit low on alk and calc no? PH?

And I'm going to assume salinity is 1.025 not 1.25.

 

[Baronen]

Yeah I want them higher. Been dosing tropic marin all in one. Don’t own a ph kit

 

[ZoixDark]

And remember we're using hobby grade test kits and +/- 10% is pretty normal so you could be as low as 360 calc and 6dhk.

How long have you have them before they started heading south?

 

[PghReef]

Phos and nitrates are a little to low, alk is fine and actually shouldn't be raised unless you raise your nutrients. That damage to me looks like some sort of nipping. A lot of people have had issues with reef safe blennies eating coral polyps. I'm not sure if it's more prevalent in tanks with no algae or not, or if it's just fish fish wild.

I think you need to pull up a chair, grab a bottle of whiskey, and watch you tank to see if you see anything picking at the coral. My bets are you'll see the blenny picking polyps off one by one.

 

[Baronen]

Phos and nitrates are a little to low, alk is fine and actually shouldn't be raised unless you raise your nutrients. That damage to me looks like some sort of nipping. A lot of people have had issues with reef safe blennies eating coral polyps. I'm not sure if it's more prevalent in tanks with no algae or not, or if it's just fish fish wild.

I think you need to pull up a chair, grab a bottle of whiskey, and watch you tank to see if you see anything picking at the coral. My bets are you'll see the blenny picking polyps off one by one.

Corals are about 2 months in the tank

I get home so late most nights I can’t watch my aquariums. I did see him once acting like the starlet coral was a piece of rock and he was just crunching on it. I haven’t seen him touch anything else but I feel like he is. He is going to be a pain to catch..

I have 4 emerald crabs that I need to remove as well. I had a bryopsis outbreak and they really helped with that. They might be picking at things now that algae is gone as well

 

[Tiki Reef Joshua]

Its the alk and low nutrients.. mostly the alk... Thats my opinion..

 

[vic5hands]

get your Alk up to at least 8

 

[PghReef]

Hard to say, only way to know for sure is observation. Crabs come out at night so going in there with a flashlight after dark will help to see if it's a nocturnal pest.
Maybe a Webcam or video to try to capture some daylight activity? Or a random day some weekend you can chill in the same room to observe?

Is your tank algae free or do you have plenty of algae?

 

[vic5hands]

Alk is low see below

 

[Baronen]

Here they are the day after the blenny was added and i noticed white areas on both. Clearly polyp extension is much better here. I test about twice a week and it’s always the same.

 

[Joedubyk]

Alk is fine. I run 7 alk.. your problem likely is low nutrients

 

[Baronen]

Tank is void of any green algae besides the glass. I went overboard with algae eaters to help with bryopsis (it worked)

 

[Joedubyk]

Its the alk and low nutrients.. mostly the alk... Thats my opinion..

Not the alk. I run 7. Have been for a long time

 

[PghReef]

Its the alk and low nutrients.. mostly the alk... Thats my opinion..

Have to disagree, it looks picked at IMO.

Some run alk in the 6-7 range with no problems. Any lower then 6 id say your in trouble but a 7 is fine. I keep mine around 7.5 and have great growth. If you raise your alk without raising nutrients you'll kill every coral very quickly. Corals adapt to lower alk much easier then higher IME.

Then again my nitrates are somewhere between 10 and 25 on salifert, really need to make a more accurate range there sali, but look closer to 10 when I check with API. My phosphates run .04-.08.

 

[PghReef]

Tank is void of any green algae besides the glass. I went overboard with algae eaters to help with bryopsis (it worked)

My best guess without observation is a hungry blenny that has no algae so is eating coral polyps containing zooxanthellae.

 

[Baronen]

Also something definitely came in with my rock. I occasionally see sand plumes coming from the rocks. Heard some crunching another time and I swear I saw something in the corner of my eye once. Rock came from the gulf

 

[Flux Capacitor]

I think your ALK is fine.

I would think it’s being picked at. If you’re hearing things or seeing things look at night. Get a red flashlight if you can.

 

[PghReef]

Could be gorilla crabs or other pest crab. Flashlight after dark will catch them. I found one munching on my lepto one night made a crab kabob. In 30 lbs of kpaquatics rock I've caught 4 or 6 total. I know there's at least 1 more I saw and couldn't get the other night.

Also I've seen lots of little plumes come out randomly. Never heard crunching though. I always figured it's one of my million hitchhikers. 99% have been good and I think really helped my tank stabilize so I'll just keep going crabbing until I never see one again.

 

[Tiki Reef Joshua]

best of luck!