Corals Dying

[Moogled]

My tank's been running for about a year now, and lately some of the corals are dying.

My Merulina plate coral started turning white on the edges and it has been slowly creeping across the coral; now it's almost half dead. I tried scrubbing the algae growth on the skeleton but it doesn't seem to be coming off. I dose Calcium regularly but I think there may be another problem. Corals don't seem to thrive in my tank with the exception of a Donut coral and a Scolymia :(

I'll post my water parameters tonight.

Any wide guesses as to what's happening or does the "whatareyourwaterparameters?" always apply?

Thanks in advance,

Marco

[michika]

What kind of lights are you running?

[Moogled]

I'm using a 36" 4 bulb Tek Light.

It doesn't seem to be an improvement from my crappy Coralife T5s.

However, the spectrum is very blue from the 2 actinic bulbs and I'm wondering if I should have three 10ks/ one actinic rather than two bulbs for each.

[untamed]

I would propose the "What have you recently changed?" question?

[michika]

I'll post my water parameters tonight.


What did your parameters turn out to be?

[Moogled]

Sorry, I went out to buy new test kits just in case these older ones wouldn't work.

I did a 30% water change two weeks ago with another 10% the day after. My nitrites were coming up as 0.25.

My current parameters are:

Ammonia: 0.25
Nitrate: 0
Nitrite: Undetectable

I do regular water changes and feed moderately and try to keep Ammonia as low as possible. I've had this tank for almost a year now, shouldn't ammonia be undetectable unless it was a spike? All my fish are fine and swim around happily. There's no odd behaviour (e.g gills showing) of any sort.

[fkshiu]

0.25 ppm ammonia is a potentially deadly spike if accurate. Re-test immediately.

Have you lost any fish lately? There may be something rotting away in an unseen corner.

Ca and Alk levels would also be helpful.

[Moogled]

I haven't lost any fish lately; they're all very healthy.

My Ca levels are around 450 and I don't have any Alk measuring kits.

However, there is some detritus accumulation in one corner of the tank - I didn't think much of it because I usually siphon my tank very clean every time I do a WC.

[Der_Iron_Chef]

Have you implemented a phosphate reactor or anything lately? Anything that could potentially initiate an algae die-off?

I could test your Alk for you if you lived nearby....or someone else could if they live nearby.

[andsoitgoes]

You just changed your lights about a month ago, you posted about that, didn't you?

Why not try changing back? Obviously that change is the only major thing youv'e done on your system.

[Moogled]

Hey guys, thanks for all the replies. :)

I upgraded to these Tek Lights under the promise of better growth because the bulbs have better PAR. Switching back to the Coralife T5s wouldn't make it better because those are fairly weak lights to begin with.

I'm beginning to think it's a chemistry issue because I have a Gorgonian frag that's been growing steadily with superb polyp extension (the frag is 3 inches long now and the polyps are nearly an inch when extended). Some corals do "good", some flat out die on me.

The other coral that seems to do well is GSP, which has quadrupled its surface area in my tank (started as a frag too).

I've taken a look at some of the chemistry articles provided here on Canreef (like balancing Ca and Alk) and I think that's what I should dwell into to improve coral health, but everything seems so steep and technical.

Where do I start? Should I change the way my setup is run?

[andsoitgoes]

Not to go backwards, but if the only thing you've changed is your lights and the corals were doing fine before that change, that's the one big thing that strikes me as a concern. How did you acclimate to the light change?

Going from PC to MH offers an increase in PAR, but if you switch from PC to MH without any adjustment, it can result in a wide range of problems. Maybe the SPS are using up more CA to grow faster in the higher provision of light, same with alk/etc. Maybe it's a combo?

[Der_Iron_Chef]

Maintaining CA & ALK hasn't been too difficult for me. The only times it's difficult is when I'm lazy and haven't taken the time to figure out how much is being used/how much to dose. Now I've settled into a pretty regular routine and I test sporadically. I don't have a calcium or kalk reactor, but dose with Turbo Calcium and Kent Superbuffer.

[Moogled]

Nick, you might be on the right track.

I put the Tek Light on the tank and fired 2 of the 4 bulbs on for about three days, then put all bulbs on.

Corals dying over time has always been an occurrence for me. Corals just won't do well for some reason.

[Der_Iron_Chef]

Have you always had that problem? Corals slowly dying?

[Moogled]

Yup. Some live (GSP, donut, gorg, scolymia). Others die.

[michika]

I'm guessing its either lighting, or something in the water your not testing for. What kind of water are you using?

[Der_Iron_Chef]

Interesting. But your fish thrive?

[Moogled]

Yeah. I've had a pair of percs for a year, a Lubbock's wrasse and some other fish that show good signs of health. I won't list the others for the sake of avoiding a debate about my fish husbandry.

I recently had an outbreak of hair algae too, does that mean anything?

[Ruth]

I suspect that you probably have a water quality issue. The corals that you say seem to do well for you are ones that tolerate a less than pristine environment. If you have a large fish bioload you are going to have nutrient issues with your water. It's not a big deal but you have to decide what you want more - lots of fish or more delicate coral.

[Moogled]

Hmm...I DO have a large bioload in my tank. How many fish should one keep in a 33 gallon in order to provide a low nutrient tank in order to keep corals?

[Snappy]

Hmm...I DO have a large bioload in my tank. How many fish should one keep in a 33 gallon in order to provide a low nutrient tank in order to keep corals?
It's hard to say what is an appropriate number as there are too many variables to that question. The real question is; can your filtration handle the bioload your livestock is producing?
If it's a bioload issue you will likely see algae blooms IMO. However if you are measuring amonia there is a problem and tank has either started to cycle or something died. What are you using for a skimmer? Is it running efficiently? Also what is your water temp? This can drasticly affect sps.