LPS Coral and fish rapidly dying, inverts and SPS seem okay.

[scoran]

Over the last week, we've run into an issue with our aquarium where our fish and coral rapidly declined. We have a 55 gal tank, that has been up and running for 4 months now. Last week we had 2 clown fish, a valentini puffer, an adorned wrasse, 2 emerald crabs, 9 hermits, various snails and a sand sifting seastar. We also have various coral, about 10 LPS frags (hammers/frogspawn/bubbles/duncans) and 2 colt coral.

The sequence of events goes as follows:

Friday, June 9th: Everything looked great, I actually commented on how well everything was looking (possible downfall number 1). We added SeaChem fusion 1/2 to raise the alkalinity/calcium.
Sunday, June 10th: Everything looked good, added calcium to bring it up slightly, topped off tank with saltwater.
Wednesday, June 14th: A few of the coral were throwing a fit about where they were at, but everything looked good. Preformed a water change like we typically do, 5 gallons.
Thursday, June 15th: We were missing our small Maroon Clown, figured he was just hiding. Later that night we found that one of our Emerald Crabs was eating him. At this point we figured that maybe the Emerald crab caught him and decided to eat him. At this point, all of our LPS coral were closing up. Some began to show skeletons.
Friday, June 16th: We noticed that our larger clown was not looking well, he was swimming at the bottom of the tank, resting on the sand. Later that night we pulled him from the claws of our Emerald Crab. Our LPS coral were completely in, showing more skeleton. Colt Coral look fine, and actually keep breaking off branches and regrowing (went from 2 to 4 colt coral frags in a week).
Saturday, June 17th: We added some chemiclean to our tank to remove some red cyano that had taken over our tank. At the same time we noticed our puffer was looking the same as our large Clown did, swimming/resting on the bottom. We thought this may have been due to the new wave makers we got (went from smaller ones to larger ones for more flow) we had them pointed at the rocks to blow the cyano off the rocks. We later found the puffer dead and our wrasse on the bottom resting. We were able to get the wrasse up and swimming and he looked fine. We did another 5 gallon water change, as most of our LPS frags were complete skeletons at this point, with barely any tentacle showing . We did an iodine dip on them, which didn't seem to help.
Sunday, June 18th: So here we are today, I just got done flushing my wrasse and doing a 10 gallon water change. Our crabs look fine, both hermit and emerald. Our snails are active, and our sand sifter is sifting away just fine. Our coral are still completely in, we have attempted to feed them mysis, but with them completely in it is hard to do. Colt Coral are waving away, having a great time.

Our current levels are as follows:

Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate: 20 ppm
Salinity: 1.023 SG
pH: 8 pH
Calcium: 440 ppm
Alkalinity: 180 ppm
Temperature: 77F
Phosphate: <.1 ppm


At this point we're not sure what caused this purge of most of our tank. Nothing has really changed, we removed the red cyano and added new pumps to help prevent it in the future. Any suggestions would be greatly appreciated.

[Sniperhank]

You have a nutrient issue going on in the system. Cyanobacteria feeds off of nitrate and phosphates in the water column in low flow zones. Enough of it and you won't ever see a reading from your test kits. Though .1 doesn't seem like much, that is still high phosphate levels. In a reef system, the goal is around .03 for phosphates.
So, I would do large water changes with ro/di water. Also, stop dosing anything into the tank. There is no need to dose anything unless the system is overwhelming with corals that are absorbing elements from the water column faster than water changes can replenish. Doing so can throw parameters out of whack and be detrimental towards tank health. Water changes will address this as well.

[54seaweed]

like hank said nitrates feed cayno bacteria and other algae's
your nitrate level is at 20ppm LPS will react as they don't like high nitrates

if your seeing nitrates you most likely have phosphates as well
the nutrient issue needs address large water changes should fix this

Reef tank nitrate and phosphate test readings should be 0 to 20ppm closer to 0PPM is best
another question why are you dosing
are you testing for what you are dosing

chemicals are like a time bomb I lost a bunch of coral from that in the past basically the only time to dose is if your heavily stocked with sps ,

I no longer dose just water changes the salt mix supply's everything you need

[melosu58]

Originally Posted by 54seaweed

I no longer dose just water changes the salt mix supply's everything you need

Same here. Also on a side note The emerald crab did not kill your clown. Only if it was already dead or close to it. A healthy clown would have no trouble getting away from a slow emerald crab. JMO

[Mebbid]

A few things:

1 - What test kits are you using?
2 - What salt mix are you using?
3 - How are you testing salinity?
4 - How did you acclimate everything?
5 - What lights are you using?
6 - Is there a refugium?
7 - How were the fish eating before they died?

It would be unusual to have 2 major problems with your tank at once, most likely it is a single culprit damaging both the fish and coral (which is equally weird that it's not hurting the inverts). If you answer the questions I think we could help you out a little more.

[Brookster123]

I have about as much experience with sw as you do but one thing that seems to ring true in most conversations is not adding chemicals or additives. Messing with chemistry is a ticking bomb imo, best to address the problem at the source (not always obvious). Getting water changed and parameters back in check should get the tank back on track. I have a small system (45 gal) with a low bioload and decent amount of coral. I've been instructed to change 5% water weekly and do not dose a thing!! Like nothing.. the wc will replenish trace elements and keep the inverts happy. Adding to many trace elements can create a toxic environment.