Poor Polyp Extension

[Jaws]

I'm wondering if there is any other possible reasons for getting poor polyp extension other than poor water quality? My water quality is good, the tank has good flow, and there's plenty of light. The corals are still growing and coloring up nicely but still have bad polyp extension. Am I missing anything?

[marie]

Do the polyps open at night? Could you have a fish picking at them? My flame angel used to pick at sps polyps, never did any damage, just annoyed the heck out of the corals :biggrin:

[Aquattro]

Do they extend at all when you feed the tank? I never figured out why my old tank was like that either, but with the new tank, every coral is extended full time. I believe it's water quality parameters we can't/don't measure, maybe disolved organic compounds. Is your skimmer pulling lots of crap? My collection cup gets about 2 inches of gunk every week, and that's with 4 fish, minimal feeding and a bare bottom. You should probably get at least that much in the skimmer.
Other things might be flow, I have tons of flow this time around. Lighting I don't think would contibute, but not sure how to verify that. My temp is stable now, maybe that helps?

[Jaws]

My skimmer has not been performing very well lately. I'm not actually sure if it's because I'm feeding very little lately or because it's just not functioning properly. I believe the skimmer wasn't set up properly for the first three or four months that the tank was set up so when I finally did get it set up properly I would get two inches + every 3 or 4 days. I was battling a lot of hair algae at the time too which I'm sure was as a result of poor skimming. It was pulling out that much for a month or two but has slowed way down now and the hair algae is all gone. I've also cut back on my feeding for the time being. I feed once a day in smaller quantities until I can verify everything is stable for a while. The polyps do fully extend on most of my corals when I feed at night with the exception of a couple less healthy ones. I notice polyps come out a little more when the MH's shut off at night too and just the actinics are on. My temperature is usually pretty stable at around 78 but has got up to around 82 a couple days this summer but not very often. I have most definitely seen my flame and coral beauty angels pick at corals from time to time but usually at the base of the coral and never concentrating on just one. If I watched the tank for 2 hours they might nip at 4 different corals in total and spend the rest of their time picking at the rocks and glass. I just added two Vortechs to the system so I'll see if that helps the flow too. I'm not sure how quickly they should respond but it's been 4 days and I haven't noticed any difference. Thanks for your comments guys. Keep em coming.

[marie]

I would suspect the fish :biggrin: . My sps corals only opened at night when I had my flame angel. They were still healthy and had lots of growth, they just didn't open their polyps up during the day.

[muck]

Im assuming you are talking about polyp extension from acropora. (or other SPS) Check your corals for Red Bugs. I had poor polyp extension from when I had Red Bugs last year. Soon as I nuked em the corals started to extend their polyps a lot more. You will have to check really really close as they are super dupper tiny.

[seashells]

IMHO water flow. Try this link http://www.advancedaquarist.com/2006/6/aafeature2/view?searchterm=water%20flow

[Jaws]

Well, I'll tell you what I have for water flow now:

I have 4 1" Seaswirls. One is plumbed to the return and is pushing about 1000 GPH. The other three are plumbed to a closed loop on an Ampmaster 3600 and are pushing about 1000 GPH through each. This is all I've had for about the last 4 months. In the last week I've added two of the Ecotech Vortechs to really try and jack the flow. They're each running at full out which is about 3000 GPH each. I would imagine this should be more than enough for a 180G tank. Since I've only been running it with this much flow for less than a week, could that be the problem or should corals start to respond to the high flow almost right away?

[rickjames]

Let's do a test, you can give me a frag of each of your corals and i will see if they have PE in my tank! :razz:

I always found that my acros took a while to respond to better tank conditions, such as better lighting, flow, water quality, etc. I have one acro that never grew or showed any PE for a year. Now all of the sudden it has rapid growth and good PE. Go figure? Strange thing is I haven't changed anything.

Either way i would give them time. My .02.

[Jaws]

Time does seem to be the best medicine in this hobby. I'll see what happens.

[StirCrazy]

Well, I'll tell you what I have for water flow now:

I have 4 1" Seaswirls. One is plumbed to the return and is pushing about 1000 GPH. The other three are plumbed to a closed loop on an Ampmaster 3600 and are pushing about 1000 GPH through each. This is all I've had for about the last 4 months. In the last week I've added two of the Ecotech Vortechs to really try and jack the flow. They're each running at full out which is about 3000 GPH each. I would imagine this should be more than enough for a 180G tank. Since I've only been running it with this much flow for less than a week, could that be the problem or should corals start to respond to the high flow almost right away?

thats only about a 55x turn over rate and thats not taking into account head loss through the sea swirls so I would say you could make that about a 40X turn over.. I would say that is a low water flow for a SPS tank personaly so it could have somthing to do with it.. I am running about 110X turn over in my tank and I think Brad is up around the same.

Steve

[Jaws]

I took the head loss into account when I said 1000gph for the seaswirls. I've seen so many other tanks out there with thriving sps corals that have a lot less flow. I figured what I have would be enough.

[reeferaddict]

thats only about a 55x turn over rate and thats not taking into account head loss through the sea swirls so I would say you could make that about a 40X turn over.. I would say that is a low water flow for a SPS tank personaly so it could have somthing to do with it.. I am running about 110X turn over in my tank and I think Brad is up around the same.

Steve

Delbeek, Sprung et all shoot for 40X overall... not that 110X is bad if you can manage a tank with that much flow... it all still pales in comparison to nature...:biggrin:

[Aquattro]

I figured what I have would be enough.

Ya, that should be fine...

[StirCrazy]

I took the head loss into account when I said 1000gph for the seaswirls. I've seen so many other tanks out there with thriving sps corals that have a lot less flow. I figured what I have would be enough.

sorry that came out wrong.. I had a nice tank with 20X turnover so I am not saying you don't have enuf I guess but rather with a loer number like that you have potential for more dead spots which could be afecting the corals some how.. now if it is all the coral in the tank and not just a few then again don't worry about it.

also one thing to think about.. how hard is the jet stream from the sea swirls? could it be to much of a blast and causeing the corals to retract?

Steve

[Jaws]

also one thing to think about.. how hard is the jet stream from the sea swirls? could it be to much of a blast and causeing the corals to retract?

Steve

I know that before I added the vortech I had to angle the flow from the seaswirl down at the rocks more in order to get more direct flow so all the turbulence wasn't just at the top. Now since adding the vortech I've gone back to a 90 degree pvc fitting for the outlets on the seaswirls and since there's so much turbulence at the top half of the tank, the currents crash into each other and force a lot of the water down on to the corals. It looks pretty good. I observed the corals last night about an hour before the MH's turned off and even though they had no where near the polyp extension I've seen on really healthy tanks, the polyps were peeking out on most of the corals so this is a good sign.