Death of a hammer coral

[chufa]

Well, my hammer coral is dead . It started receding about a week ago, and slowly shrunk into nothing. This is the first coral I lose, and all the others are fine. I am trying to figure out its cause of death. There are several possibilities, and perhaps you could help me here. I appreciate your input and opinion.

 

1: Xenia. The hammer coincidentally started receding right after I added Xenia. The Xenia grew very fast, and I had to trim it down. Could be that the Xenia released some toxins the hammer was intolerant of. The argument against it is that there is a closely related frogspawn which is thriving and lies even closer to the Xenia.

 

2: pH. All my tank parameters were perfect except pH which was on the low side (7.8-8.0) for the period of time the hammer was receding. The pH and Alk are fine now, but too late for the hammer. My pH was fine until the period right after I added the Xenia, when it dropped a bit. During the period of low pH, everything was fine with the rest of the tank except the GSP seemed to be not fully open at times.

 

3: Frogspawn. My frogspawn has grown huge. It spreads over 7 inches across, and given the dimensions of the Eclipse 12 tank has the potential to sting everything in the tank. However, the Xenia is also growing huge and is even closer to the frog than the hammer, and the hammer is closely related to frogspawn (both Euphyllia sp.) and may tolerate each other.

 

4: Light. The frogspawn dominates the center of the tank, and the hammer was more on a corner receiving less direct light. Both were close to the surface however.

 

I figure it could be a combination of some or all of the above.

 

Here are my tank's parameters:

 

12 gallon Eclipse (4 months old)

Eclipse filter + Rio 90 powerhead

32W CSL Supernova Smartlite retrofit light

20 lbs LR (Florida aquacultured)

20 lbs LS (aragonite)

Livestock: small ocellaris, yellow-tailed damsel, peppermint shrimp, 5 hermits, 4 snails (2 bumblebee, 1 astrea, 1 turbo), emerald crab, caulerpa, frogspawn, xenia, GSP, various small hitchikers and formerly, a hammer.

Tests: ammonia, nitrate, nitrite: 0. pH: 8.3 (previously 7.8-8.0), total alkalinity: 180, 1.0245 SG, calcium: 450 ppm, Temp: 78-79 C.

Water: Coralife salt added to supermarket distilled water, 1.024 SG, supplemented with reef iodide and aragamilk, premixed an aereated overnight. 2 gal/week waterchanges.

 

Sorry for the long post. Might as well put all info here that I can from the beginning.

[Mnesarchus]

This might be a really stupid comment.. But I think I read somewhere that frogspawn and hammer wont sting each other because they are the same genus.. does that sound right at all?

[tinyreef]

i'd be guessing a combo of issues, especially since your frogspawn is thriving. ??? light, water flow, positioning, water content (i.e. caulerpa), and the low pH : especially the last one but it's a little confusing with the frog and xenia doing well.

 

where was the hammer in relation (water flow-wise) to the frog and xenia? mid-stream (flow origin/destination-wise), upstream, or downstream? i'd guess down or at least mid-stream based upon the info so far.

 

how about that clown? did it try to guest with the hammer? how about picking at the gastro discharges? the corals really hate that ime.

 

just tossing darts against the wall right now tho. sorry about the loss.

[BCOrchidGuy]

I have no ideas just sorry that you lost the Hammer.

 

Hope you get it figured out.

 

Mnesarchus, that isn't a stupid comment at all, I've read that as well and it makes sense. From what I understand most corals in the same Genus Family or species can't sting each other because the chemical they use is the same IE if it can't sting itself it can't sting another Euphyllia.

[chufa]

Thanks guys. Tinyreef, it is hard to say whether it was downstream or upstream. The eclipse filter flow and the powerhead are on the opposite sides directing flow towards the center, where it kind of whirpools. The xenia is on one side, near the powerhead, and the hammer was near the eclipse flow on the other side. The frog is in the center.

 

The clown never touched the hammer. Its "host" is the powerhead;)

[tinyreef]

ok, i have a better mental pic of the tank now. correct me if i'm wrong:

 

the eclipse outflow was over (after) the hammer flowing towards the front and the PH on the other side was flowing across the tank. that would place the hammer 'downstream' with low/med. flow as i see it. the xenia would be in a high 'negative' flow (PH and eclipse uptakes) and the frog in a high turbulent flow (convergent outflows).

 

did the hammer slowly lose color or just quickly recede and liquidfy/slough?

 

also it seems to have been in the shaded portion. did you feed it or the tank in general? it may have been starved from low light and/or low food.

[chufa]

Hi Tinyreef:

 

Your flow interpretation is very good. The hammer never lost color; it receded and then liquified. I never fed it. I tried unsuccessfully. I feed my frogspawn some frozen fish once every 1-2 weeks.

[sjpresley]

First, I hope you didn't take the "dead" skeleton out.

 

Random question. How often do you feed your peppermint shrimp (assuming it is a Lysmata wurdemani)? They are carnivores and will eat corals too if they are hungry.

 

I had to single head Euphyllia ancora frags that I placed together that were doing great. One started receeding and I noticed my L. wurdemani gong after the tissue were it was receeding as soon as the light went out. I could also see little "hammer heads" that had been torn off floating around the tank. The pieces of Euphyllia were responsible for loss of some ricordia mushrooms they landed on and stung to death. A couple weeks later the same thing happened to the other head.

 

Everything else in the tank has done fine throught this whole incident.

 

Back to the "dead" skeleton. Both of my Euphyllia heads are coming back. The first one has dozens of small heads ringing the old skeleton. They started out as little brownish/red dots and are now a bunch of crowed guys that expand to 5-6 mm during the day. The second head is in the 2-3 mm stage of regrowth and hasn't as many heads but there is live tissure regrowth going on.

 

If you read a lot of stuff written by Eric Borneman, you will become less afraid (if you aren't already) of "overfeeding" your corals and other charges. And you will gain a better understanding of nutrient cycling in reefs. What most people term proper feeding starves many of their animals because they are seeking low nitrate levels. If you look around you will see that coral biologists (NOT aquarists) will tell you that there is no evidence that nitrates up to 80 ppm and higher will not harm any corals.

 

Sorry, I digress, I started increasing my night feedings, gradually, and now feed tank at night about 4 times a week instead of once and haven't noticed any negative signs (no increased algal growth, just big expanded corals, and reproducing zooanthids and encrusting gorgonians). My tank has a very heavy bioload (10G, 2 fish, 1 shrimp, various crabs, probably dozens of snails, with SPS, LPS, leathers, shrooms, the whole bit, just crammed in there).

 

Okay, I digress again...

[chufa]

I have kept the skeleton. it acts like a piece of "live rock". it has stuff growing on it (coralline, sponges, tube worms). The peppermint shrimp never touches the corals. I've kept a good eye on him. He eats pieces of pleco pellets I give him every other day.

 

What do you feed your corals?

[sjpresley]

Corals don't have to have big pieces, and if you have food theives such as Lysmata all the better not to use them.

 

I mix daphnia, brine shrimp, blood worms, krill, and spirulina formula cubes to feed my fish. I let 1 or 2 cubes of each thaw in a small plastic container, mix it all up with some vitamins and a little extra salt water and refreeze it. Then I just squirt a little tank water over the mixture and suck up whatever thaws into the non-frozen water and feed the tank (Note: despite all of this feeding the tank hasn't grown but is still only 10G, the creatures inside, however, have grown considerably). I usually aim food at some yellow polyps, mushrooms, Tubinaria, Blastomusa or whatever has feeding structures out during the day so they can catch a few pieces and get some of the "juices" which have very small particles that will stick to the coating of most corals. I do the same when I feed the tank at night with Tubastraea, Caulastea, Trachyphylla, etc. So most of the food goes to the fish, shrimp and crabs, but I take the opportunity to give the corals first shot. I also feed phytoplankton and Microvert sporadically, sometimes during the day, sometimes at night, and aim it at corals that are open at the time. When I am out of the stuff I have right now, which will take some time with only a 10G to feed, I plan on trying Eric Bornemans Homemade coral ration on pgs 64-65 of Aquarium Corals.