Green Star Polyp Not Opening

[FirstContact]

I'm new to corals and have about seven frags in the tank. I bought some Green Star Polyp last Saturday, but it's not opening. I was looking for suggestions on what it likes with regards to light and water movement. its on a rock four inches above the sand. Tank is 20 inches deep not including sand bed.

System parameters

T5 4 bulbs 12k 12k 14k 20k
Ca using RC it's 520 but I don't know why so high
Salinity 1.027 using a glass hydrometer
Phosphates were 0.08 but now 0.01 after large water change (Hach PO4 test kit)
Nitrates not measurable on a scale of 1 -10 ppm
Temperature fluctuates from 74 -78 degrees during the day night cycle

After the phosphate level was reduced by a large water change the mushrooms, and two hammer corals shrunk up. Xenia is still doing good.

 

[InsaneClownFish]

What's your Ph and Alk?

 

[FirstContact]

Alkalinity is 9.3 dKH

I haven't been testing for pH recently, just alkalinity. If the alkalinity is good, does that mean the pH is good. I don't have a calcium reactor, so I figure the pH doesn't fluctuate much.

 

[InsaneClownFish]

Well yes and no. Although I am guessing your Ph is fine. I would try dropping your SG to 1.025 and Calcium, while high, I'm not sure this would contribute to them not opening. Have you tried moving them to a different spot in the tank? If they're blasted with too much flow, or light, they may not open.

 

[FirstContact]

Hi InsaneClownFish,

I just went downstairs to test the pH. It's about 8.2 on a Red Sea color test.

I thought everyone recommended higher salinity for corals? Which is weird because I thought my salinity was low at 1.024 or 1.025 and I raised it to 1.027 which is when they shrunk. In the books I read, they recomend 1.027. I'll see how they look tomorrow and drop the salinity if they don't look better.

 

[FirstContact]

I'm guesing you might be right with too much flow for the Green Star Polyp. I'll try to find somewhere with less flow.

 

[InsaneClownFish]

I keep my softie reef at a specific gravity of 1.025-1.0265. In many respects I keep my tank higher than most people. It's acceptable to keep a tank anywhere from 1.023-1.025, although I personally feel that 1.023 is a bit low.

1.027 is definitely on the high side. Let me know how they do when you move them from the flow.

Keep in mind that sometimes the simplest explanation ends up being your overall solution. If you noticed the difference after changing your SG from 1.024 to 1.027, then one of two things is going on. They really like being at a SG of 1.024, or the change was too rapid and it will take them time to get used to the higher density of water. Either way, I recommend dropping it to 1.026.

I hope this helps.

 

[Ethan_W]

i agree with dropping it to 1.026 and keeping it between 1.025 and 1.026 at all times. my GSP however is doing well in fairly direct flow from my Koralia Evolution 750. it is faced away but gets a lot of movement, especially the edge of it that has grown over the top of the rock and is right in the flow. it opens every morning as soon as the lights come on and has grown rapidly in the past 3 weeks (more than doubled from original size!)

 

[d0ughb0y]

just set it in one place and leave it alone, it can take up to two weeks before the polyps come out. if you have been touching it, moving it around frequently, that will only make it take longer before the polyps come out.

 

[FirstContact]

Great suggestions everyone. I added some freshwater tonight. I have been moving it. I'll leave it alone for a few weeks and see how it does.

 

[alancolinet]

You may also want to consider this as well:

T5 4 bulbs 12k 12k 14k 20k

I would recommend having at least 1 actinic bulb in there.

While Green Star Polyps are a hearty soft coral, they are rather picky when it comes to water parameters. Mine didn't start spreading and growing until I had my phosphates reduced to 0.0 (Rowaphos) and my nitrates reduced to less than 20 ppm.

Definitely reduce your salinity to 1.026 (full strength sea water). I keep mine at 1.026 due to having lots of brittle stars (Bob Ferners recommendation).

The temperature shift of 4 degrees is a little much, however, if the tank always does this.. then it should be fine (consistency is key).

Otherwise, everything else looks good.

Good luck.

 

[carlosR]

I have a couple colonies of these and noticed one was not opening and when it did it quickly shrunk. Answer: nibbling fish! I had gotten negligent in providing seaweed for them to tear up. I moved the offended colony, provided Nori and watched as my tang and angelfish tore up the Nori sheet. Now I have happy green star polyp colonies and they are once again thriving. Also, I think your salinity was too high, lower it down to 1.024 or something close that you are comfortable with. These corals seem to enjoy moderate flow. I've got small colonies scattered throughout the tank and notice that those in high flow areas stay small sized, those in low to moderate flow are growing.
Good luck and enjoy them.