72 gallon reef experiences first major loss...

[mikeguerrero]

Hi Reefers,

I'm really in shock after comming home last night with a new edition to add to my reef; I purchased a blue coral banded shrimp on the advice of one of my reputable LFS.

As I am acclimating him to the tank I notice that my largest SPS coral on one entire branch is completey recessed and pale white.

I immediately remember my brother saying why are the tips on this SPS look white; I had told him the corals grow out and this is common for SPS corals.

But this was different, one entire large branch was dead and the other branches were dying from the bottom up.

I then stir up a batch of coral dip that disinfects my corals from bacteria and other common pathogens. I soak him in the dip for about 30 minutes and then notice that I must frag the remainder of the colony that's alive.

I frag the best I can and transfer the healthy frags to my pico as it's been cycled and doing well, and nothing other than live sand and live rock.

I then carefully examine all my other SPS corals and notice nothing at all out of the ordinary. With this relief that it's just one coral I begin the process of elimination.

Out come all my test kits and I begin the analysis.

Specific Gravity 1.023 (Normal)
Water Temp 76.5 - 79.5 in 24 hour period (Normal)
Ammonia 0 ppm (Normal)
Nitrite 0 ppm (Normal)
Nitrate 20-25 ppm (Bad)
Calcium 400 (Normal)
Kh 9.0 Dkh 3.2 Natural sea water should be Kh 8 and Dkh 2.44 (Normal)
PH 7.9 - 8.3 in 24 hour period (Normal)
Phosphates .03 (Normal)

My tank is sealed from glass lids so I don't suspect any type of airborne junk to fall on the surface and get pulled into the tank.

My skimmer and all other filtration check out fine.

So my finger goes right to the high level of nitrate; but I hesitate and think why are the other corals fine and just my largest branch coral bad.

And then it hits me; since the introduction of my blue tang and my school of chromis they have hosted the corals branches every night.

The tang would take the center body towards the bottom, while the large two chromis would take the side branch; the one that has completely bleached.

I've also noticed that these two particular chromis, only these two have burnt spots on there scale as if something has been stinging them; but I couldn't place what.

So my conclusion is with the elevated amount of Nitrate in my tank and the fish bothering the coral every night; it was the catalyst that did him in?

I ask all the gurus out there to help me out; am I on the right track or am I off?

Keep in mind that the polyps on the other sps are out but I'm wanting to believe they would be more out if the nitrate was below 10.

Mike G.

p.s After work, I plan on doing a 10 gallon water change for 7 days straight, that should drastically help out the tank from Nitrate. Any body have other techniques to lower Nitrate?

 

[sadielynn]

Mike
NitrAte at that level are not all that bad but high
what I would recommend would be a bag of chemi-pure and if you have it already get a new bag as well as possibly a second filter with an addtional 1/2 unit. I would think that the 10 gallons per day might be a bit much maybe 5 slowly dripped in. Sorry to hear of your loss keep us posted

 

[aromano]

Mike,

Your nitrates are definitely on the high side, but you may want to choose to gradually bring those levels down with 3 - 5 gallons p/ day, since the other corals and fish are doing well. Your tank is bit over stocked and even with all the high-end filtration system and a highly efficient skimmer such as yours, the average reef tank usually has plenty of nutrients to go around and raise the nitrate levels fairly quickly. You might want to consider doing water changes more often to keep your nitrates at a lower range.

As far as the large SPS coral, it seems like you are on the right track. I think that a combination of the hosting fish constantly irritating the coral, along with the nitrate levels on high side might have contributed to the dying coral. I think it was a good idea to dip the coral and frag the remainder of the colony. Hopefully it will give it a chance to recover from the stress.

P.S. I had a coral banded shrimp once (not a blue one) that was doing fine as a juvenile in my tank until it got bigger. The shrimp started showing aggression towards the fish and killed my two cleaner shrimps and a fire shrimp.

I'm sorry for your loss. :cry:
Keep us posted on how the tank is doing and if the coral is showing any signs of recovery.

 

[mikeguerrero]

Andre,

I have the blue coral banded shrimp it doesn't grow bigger than a cleaner shrimp. How did you CBS kill all your shrimp in such a big reef?

Mike

 

[Anonymous]

i doubt the tissue loss has anything to do with your fish or nitrates. fish unless they become a constant irritent like nipping or say a clown hosting in an LPS have little effect in a big tank. And although you would maybe like your nitrates a little lower they are not bad at all mine run that high often and i have far less fish load then you and it has no ill effects. The cause of your tissue resession is one of two things, both i spoke of in other threads. 1) light shadowing - large corals can overshade themselves under the point sourse type lighting of MH - this is a common occurence that others will confirm. 2) lack of flow - sometimes because of the rockwork or once again the coral itself water movement at the base of a coral gets greatly reduced and therfor the coral doesn't get the food, o2 ect, and rid of waste products it needs. fragging is a great way of saving corals like this. the smaller pieces will grow in reaction to the light and flow of your tank and be all the better for it.

 

[aromano]

I had an orange and white CBS in my NC24 (not a smart thing to do), which did fine for about two months. It got pretty large and did kill the cleaners, which were a lot smaller and were introduced after the CBS. The CBS is a reef safe critter and should do fine in your reef even though they might show aggression after they become adults. I made two mistakes; put a CBS in a small tank and introduced the other shrimps after the CBS, which caused a conflict in such a confined environment.