GSP Not opening...worried?

[HarrisonMG]

I've had a large GSP tile for about 3 mo, all my params are stable.

Previously, as in maybe 6 mo ago, I had a full ricordea colony die out over a couple weeks for no apparent reason, and then my patch of GSP withered away too. Both of these events began with the polyps suddenly closing after having been in the tank for a couple months.

Now, I have a big tile with no open GSP polyps, lights have been on for hours. Past couple days it's been slow to open up but it did it after an hour or two. Now, almost nothing.

I checked every param I can test for--ammonia 0, nitrate between 5 and 20 (honestly, I miscounted the drops 3 times) but usually around 7, calcium 470, phosphate 0.03, and alkalinity 6.5 (It was 8.5 for a while, didn't check for a couple months, now it's this and I believe it decreased very steadily, as a year ago it started at 12dkh)

I wonder if the alk has anything to do with it since its so low, but I have 8 corals in the tank and only GSP is showing any issues. Others are zoas, palys, hammers, Xenia, candy cane. Fish look fine.

Should I be worried? If it's dying, The only thing I can think to do is move to low light. But GSP loves high light, is mid-tank rn, and has been there for months! Just.....it's happened before, and I want to stop it if I can!

Thanks if you got any input!

 

[FishAndPhysics]

You alk is low and your calcium is sorta high. Where are they coming from? Two part? Water changes? I would check your magnesium if I was you. I don't know if that can screw up GSP, but generally worrying.

 

[HarrisonMG]

Yeah I would've thought it should be a different coral that would respond to that first. I've been doing auto water changes for the past couple weeks. Maybe I made a bad batch of water? I use instant ocean sea salt, mix in RODI water until correct salinity but I will test the reserve's water tonight.

Do you recommend any products for raising the alk? Funny since it was so high a year ago it killed many of my first corals. I would figure I have to fix this then identify the source of the issue too....

 

[FishAndPhysics]

I agree, test the alk of your water change. If that is too low as well, salt mix can separate, I would suggest shaking/stirring your salt mix before you pull out what you need. If the alk of your water change is normal, I would again suggest testing your mag.

For what it's worth, years ago, I had Xenia growing in my tank like a weed (I would pull out a sandwhich baggie full of it a week and chuck it in the garbage) and then slowly it stopped growing in my tank. These polyp-y corals are a bit funny sometimes. In my case I think it was that I got my nitrates really to zero and they didn't like that, but your nitrates seem plenty high.

 

[jaybfresh]

When the alkalinity drops below 7 dkh, problems can start. Use baking soda to raise it.... don't use any 2 part solution or kalk because you don't want to raise your calcium.

There's a calculator on BRS to find out how much to dose, but try to do it slowly over a couple days

 

[HarrisonMG]

Checked saltwater reservoir--11 dKH
Added 1 tablespoon baking soda to auto top off, so it will take a couple days to go in and rise to 8 dKH.

Everything that my tank has in the filtration department:
-Filter socks
-Skimmer
-GFO
-I don't dose anything, mess with anything...just got the AWC going at 1GPD

Now, is there generally a root problem to this? I mean, my AWC params are exactly what the box says, I have a few corals, lights are on 5hrs a day and 10hrs a day when there's very little algae growth for a few weeks.

*FYI salinity 1.025

 

[ajoe]

My GSP will close for a few days at a time every so often. It's possible that it does so at the beginning of a growth spurt. They always come around and look just fine when they do. Pretty tolerant of most environments but I would not rule out parameters being the culprit. I would bet it will come around in a day or two.

 

[HarrisonMG]

Yeah hopefully. Will update.