Dying SPS frags

[robbyville]

Hi folks,

Hoping for some advice today!

I have started buying our first SPS frags from a reputable local shop. I purchased a small piece of what I believe is Digitata (Fluo green with grayish polyps). It is about an inch long and mounted to the typical disk.

I mounted the disk to a piece of LR near the top of the tank in the middle of the current from the return line. There is quite a bit of current going all the time (No Wavemaker). the first two weeks the polyps were out all the time, so much so that the frag looked like it was covered in fur. A few days ago the polyps started to not come out, and the entire piece looked a little gray. Yesterday my wife while cleaning, turkey basted the gray away, I am now left with a very white looking coral skeleton with maybe a little bit of green on the base.

I imagine the little guy is gone but I sure would like to know what is going on. All other corals and one Derasa clam seem to be doing quite well, although this is my first foray into SPS.

Parameters are as follows:

Tank: 60 gal Uniquarium (Sump built into back of tank)
Circ: Mag 9.5, and two small powerheads for extra aggitation
Lights: 2x250w 10k MH's and 2x96w Acitinic PC's
Skimmer: Prism Pro Deluxe (I know)
CA: 420
NA: 10ppm
Alk: 8.0
Spec: 1.025
Temp: 78

I will try to post a pic tomorrow and unfortunately I have not tested PH in a long time so I will try to do that as well. In general though I do not add any supplements to the system other than some phyto and coral vite a couple of times per week. I maintain all parameters through water changes and have not had any problems which is why I guess that I've neglected to check for PH!

Any thoughts would be greatly appreciated.

Best,

Rob

[Aquattro]

Waht is NA? Check the pH as soon as you can and let us know.

[Chad]

Waht is NA? Check the pH as soon as you can and let us know.

NA = Nitrate

I think :biggrin:

Chad

[robbyville]

Yep, in my world NA is Nitrate, did I use the wrong abbreviation?

My Nitrates seem to hover around 10-25ppm, I'm not sure why I can never get them to 0, but I was told recently that my derasa clam needs some nitrates for survival. I'm not sure how to balance that though since I have always been told that corals need 0 Nitrates.

NB, all the frags and clams have been purchased through J&L, they seemed more than healthy under their lights but since I don't get down there often I don't get to cherry pick like some of you lucky people :cool:

I'll get that PH to you as soon as I get home, I'll try and snap a pic as well but the lights will have already gone off!

Best,

Rob

[robbyville]

Hey guys, out of my own curiosity... Does PH shift frequently? I had always thought that since I don't use supplements that I did not have to worry as much. I think that the last time I checked ph was at least 4 months ago. Come to think of it though, a lot has changed in the tank since then i.e. New lights, Summer temps, etc.

Rob

[Aquattro]

pH can shift if you have alot of photosynthesis happening. Day to night swings can get fairly large, although going into dangerous values is rare.

[robbyville]

Thanks Brad,

So PH is on or about 8.2 which I believe is supposed to be normal. I was unable to take any pics so maybe tonight. Still, all the pic would show is a relatively white SPS coral skeleton. My main hope is to get some insight as to what my problem may be. Are there other things that I should be testing for?

Thanks,

Rob

[MalHavoc]

How long has the tank been up? Many new tanks have difficulty keeping SPS corals alive due to immature water conditions.

You may want to increase your tank circulation. Many (not all) SPS corals live in natural environments where they get pounded by hard current swells, and if they do not experience these sorts of things in the aquarium, they can suffocate. Montipora isn't normally an SPS coral that requires huge pounding currents, but I question whether you're giving your frags the current they need. I'd aim for > 20x the tank volume in total circulation, per hour, and even more if you can swing it.

Have you measured your phosphates? phosphate levels that are detectable can impede calcification and prevent the growth of stony corals.

If you're worried about your nitrate, I'd either plumb in a refugium, add a deep sand bed some place, cut back on your feeding, or upgrade your skimmer. You're not using tap water, are you?

[robbyville]

Hi Jason, thanks for the thoughts,

I have not tested for Phosphates in quite a while but will do so tonight. The frag in question is right in the middle of the tank, so I was actually worried that it had too much current from the return line. Since I have no wavemaker I thought that the reason polyps stopped coming out may have been to get some respite from current.

Here is how the system is set up presently current wise:

The tank is 60 gallon but the sump and fuge are built into the back and take up about 7 gallons of that amount. The return pump is a mag9.5 with about 6 inches of head so that alone is about 13 times volume. The duckbills from the return branch off in two different directions but essentially push the water from the right side of the tank to the overflow located on the left side of the tank. I have a maxijet 900 across from the overflow up high so that pushes water back towards the return (Lots of movement). Lastly, the other day I added a small hagen power head down low below the overflow just to get some more current lower down in the tank.

I hope that this is enough current but I guess my next investment should be a wavemaker of sorts. I use RO/DI water but the reservoir is actually outside (covered), on a covered balcony. It seems pretty clean with no dirt in it but do you think that particulate matter could be getting into the reservoir?

Lastly, the tank overall is about 1.5 years old. However it has been moved twice, once from California to Whistler (November '02), and then again just a few km away (June '03). Each move went very well with at least 50% of the water being saved, keeping all the rock and all the sand.

I'm not sure how much the moves would affect the tank, I would imagine that the cross country one resulted in some rock die off, even though it was kept immersed in water throughout.

I hope this answers your questions Jason, please keep the thoughts coming! I am presently holding off on buying any new frags until I get this figured out. I'm also watching the remaining ones closely!

Thanks,

Rob

[MalHavoc]

Hmm, thanks for the answers. I had another question for you. Do you know what sort of lighting the frag was under before you acquired it? It might have RTNed due to vastly different light intensities.

It's possible that your water is becoming contaminated. Have you tested it with a TDS meter to see if there is anything dissolved in it?

[robbyville]

Hi Jason,

thanks for the thoughts. The frags were purchased at J&L, they were in their SPS tanks which I believe are illuminated with 400w (not sure if they have one bulb per tank or two). That is why I originally mounted it so high up in the system since I only have 250w bulbs.

I have not measured TDS as I do not have a meter. I think it's time that I get one though, I think I saw a special at J&L's. I wonder if it's also time to change the filters in my RO/DI, one of them is starting to get a slight yellow tinge to it.

Can you tell me what RTN stands for?

Thanks

Rob

[MalHavoc]

RTN stands for "rapid tissue necrosis" which is something that can happen to an SPS frag. Some SPS corals like Acropora can just shed all of their tissue, from the base to the tip. Happens in a couple of hours or so.

[robbyville]

That definitely sounds like what happened, when it seemed like the flesh had turned gray and my wife turkey basted, it just came right off :cry:

I am trying to reach J&L to order a TDS and maybe a refractometer. My Hydrometer is over a year old so maybe it's time to get a new one!

Best,

Rob

[robbyville]

TDS Meter ordered, new PH test (Salifert as well). I guess we'll see what happens with the other frags.

Rob

[robbyville]

Any reason in particular for RTN to happen? Water quality?

Rob

[MalHavoc]

Whole pile of reasons why it could happen. Poor water quality, different lighting conditions, allopathy from other corals near by, temperature swings, too hot/too cold, etc.

[robbyville]

Gotcha, too many reasons to count!

TDS Meter came in today so I'll check my RO/DI when I get home. I guess that I should check both the reservoir since it's outside, and then fresh from the output to see if there are any contaminants.

Do people check their freshly made salt water or is that not needed?

Rob

[Jack]

No, you don't check your saltwater for TDS. You test for purity of your top-off water or water source... hoping for a low number.

[robbyville]

Thanks guys,

So my Reservoir water is at 12ppm and my output from RO/DI is at 5ppm. The filters and unit were bought new in December, so I guess that it's time to order new ones. Do you think that this could be part of my problem?

Rob