Red Alert! 100 Gal reef tank crashing!

[Jerome]

I helped my brother set up his 100 gallon reef tank about 10 months ago. He's running metal halides, Tunze protein skimmer and wave box, calcium reactor, refugium, no sand, and his tank did great for 9 months.

Two months ago, while he was on vacation, his RO top off unit leaked at a joint into his sump and it crashed his salinity, but nothing died. Then we raised it as prudently as we could to 1.024. About a month later, all his fish died within an hour of each other. After some investigation I determined that the detritus smelled like sulfur so I deduced that this was caused by an inoxic region probably in relation to the salinity crash that happened before. It released hyrdrochloric acid which explains the sulfur smell as well as the fish dying. So we broke open a couple of rocks, but there were no black anoxic regions in them.

Since this event, he has done multiple water changes including watching the tank very closely and increased his current and we tested his water for the following: calcium 500, phosphates 0, ammonia 0, nitrites 0, nitrates 0, copper undetectable, salinity 1.024, silicates 0, DKH 10, PH 8.3. In addition, we added prime by C-Chem, a dechlorinizer, in recommended dosage. We added 5 chromus and they all died within three days. Everything is enclosed-- no exposure to pesticides, chemicals, etc. The temperature has been 76-77 degrees consistently and his aqua controller confirms this. We have checked and double checked it.

His corals are doing medicore but none have died up to this point (LPS and softies).

I've thought of everything I can and I have never ever encountered anything like this!

Anyone have a clue of what could be causing this?!

 

[MrPex]

Just FYI, hydrochloric acid doesn't get formed in that environment and it doesn't smell like sulfur. You probably meant to say hydrogen sulfide. (If he has free chloride gas in his tank and the temps required to make HCl, he has bigger problems than his tank crashing! lol...)

Sounds like the salinity crash COULD have lowered the pressure on the gases trapped in the sand bed just enough to cause an outgassing, but the tolerances between the pressure that was holding them in and what would release them is very slim in water that shallow, and with the relatively small delta in water weight, that probably wasn't the actual cause.

Maybe some sort of biological or chemical process that's atypical in a normally salinated saltwater tank occurred during the hyposaline period that created some extra H2S, or maybe, coincidentally, one of the tank inhabitants (you didn't list what he has) happened to stir up a section of sand bed that had a healthy (but unnoticed) collection of detritus.

I'd keep the water fish free for another month or so, keep doing heavy water changes, stop dosing and just let things sit until the coral start looking healthy again. If something makes a tank look like it's hurting, no sense in guessing and adding anything other than clean saltwater.

Just my two cents.

 

[BigJay]

Sounds like the salinity crash COULD have lowered the pressure on the gases trapped in the sand bed just enough to cause an outgassing, but the tolerances between the pressure that was holding them in and what would release them is very slim in water that shallow, and with the relatively small delta in water weight, that probably wasn't the actual cause.
.

if I read it right tank has no substrate. I also can't tie the fish dying 1 month later after the correction to the hyposaline period. Unless the hyposaline period weakened the fish and opened a pathway to some sort of infection. In which case keeping the tank fish free for a while would be the smart course. But that too would be strange for all the fish originally to die on the same day within an hour of each other a full month after the event.
What did the fish look like when they died? Sounds to me like something caused a bacterial crash in the tank and ammonia built up to a toxic level. Adding 5 chromis at once caused the same issue again. I see your ammonia,nitrite results were at 0 but did you test on the same day the fish died?

 

[DaveK]

I agree with BigJay here. Obviously the tank is way out of balance, and killing the livestock. In addition a lot of additional chemicals were added. This is not a good thing to do in a reef.

Rather than try to fix the existing setup, I recommend they you tear down the entire system and set it up from scratch. Cure your live rock again by placing it in another container with SW, a heater, and a powerhead or two. Then add a deli shrimp and let it decompose. Drain and clean the tank, discarding all filter media and replacing it. Check all equipment for possible problems.

After the ammonia and nitrite in the live rock vat peak and go back to 0, wait a few more weeks and set the tank up again, using RO/DI water. Replace the LR and start slowly restocking.

 

[Jerome]

He tested the ammonia 0 before and after the the last fish died. And again there is no sand bed he has a bear bottom tank. I think we are going to tear down and start over. :cry1: Seem no way of figuring this one out.

 

[astiesi]

Did he check all his equipment for failure,...could have been due to a failed heater/pump introducing 120 volts to the tank.

 

[Boomer]

We added 5 chromus and they all died within three days.

So, where did these come from ?

We may all we jumping the gun here. These fish could be he issue not the tank. This has happen many times before on mail order fish, which at times are famous for the disease Uronema marinum. They kill fish within a day or two.

 

[MrPex]

Woops, missed the no substrate in reading the stats.

An ammonia reading of zero and then 5 chromis dying within 3 days due to high ammonia? Doesn't sound right in a 100 gallon tank unless the 0 ammonia reading was incorrect or something was wrong with the fish, like Boomer pointed out.

But at any rate, there WAS H2S in the tank, but with a pH of 8.3, he's a little basic, so any residual H2S is probably gone, although there are cheap H2S testers at water purification dealers. But I don't know what "acceptable" limits would be for a tank.

But at any rate, like what everyone keeps saying, I'd just keep doing water changes and wait until the coral looks happy again before adding any more fish. If it is something like a bacterial bloom, hopefully it would have subsided by then due to lack of hosts.

 

[robpam]

In addition, we added prime by C-Chem, a dechlorinizer, in recommended dosage

Adding this helps but your tests will not be accurate, this will nutralize your ammonia but any of your test readings will be off as well.

Someone correct me if I'm mistaken

 

[Boomer]

robpam

That is only for some ammonia test kits, such as those that use the Nessler's Method. Those that use the Salicylate Method are fine.

 

[robpam]

Boomer,

Thanks, good to know

 

[BigJay]

robpam

That is only for some ammonia test kits, such as those that use the Nessler's Method. Those that use the Salicylate Method are fine.

assuming you know the difference between the two and what tests kits use what. Hey I'll be the first to stand up and say I don't know the difference, could you explain that Boomer?

 

[robpam]

http://www.hach.com/fmmimghach?/CODE:EX_NITROGENAMM1436|1

Here is a link, I happen to use the Nessler method