Something is murdering and eating my fish.

[LesPoissons]

Did you treat your fish with anything before adding it to the tank? If it had internal parasites or any diseases it could have easily died of that and passed it to other fish. The fish could have lived with it for a while and eventually succumbed.
Or, your nitrogen cycle wasnt complete when you started the tank (if you are using faulty test kits- how would know?) And you have only been keeping levels down with water changes and once you added another fish it overcame the delicate balance you had going. If you just started the tank about 6 months ago and put a bunch of fish in a month after (including a mandarin- which usually need more mature tanks) I would guess that you overstocked before your nitrogen cycle could catch up and ammonia has been slowing building up. Hard to tell.

1. Test the ammonia with a better kit, plain and simple.
2. Do a water change if needed for the ammonia and get media that absorbs it.
3. Let the tank rest with no new additions for a while until it stabilizes- like 3 months.

 

[LARedstickreefer]

If it’s not ammonia, it’s just GOT to be the marine chupacabra.

 

[Gavin Automata]

Why not just buy a better ammonia test kit, to be sure? I don’t get this grand standing...

I posted this at nearly 9 my time, where am i gonna go buy a test kit? I mean today sure but lol

 

[Gavin Automata]

What size tank? And what are all the fish and inverts? How deep is the sand by the rock you moved?

24g. A clownfish, wheeler goby, mandarin, and previously a firefish and tail-spot blenny. I have a few blue legged hermits, a cleaner shrimp, a peppermint shrimp, some assorted snails, and a pistol shrimp. Sand is about 1 1/2 to 2 inches, varies because my pistol shrimp is a monster.

 

[99Problems]

.25 isn't a little bit of ammonia. I would get that under control 1st then see what happens if it was me.

 

[MnFish1]

You might consider a better test kit than the junk API.

Even an ammonia badge would be more accurate.

If you truly are exposing your livestock to .25ppm it's not good. If you work in a fish store you should know that. Anyway just trying to be helpful.

How long has your tank been running?

Right. The only way to know it’s a false positive is to get a better test that reads zero. Different Fish tolerate different amounts of ammonia. Corals can also tolerate low levels of ammonia but to the OP ime the most often cause of what you’re seeing is not a hitchhiker killing the fish. It’s aomething killed the fish- (disease-to which the other fish are immune) or ammonia or something else. I think people are just recommending that you consider all of those pointa

 

[MnFish1]

It’s a test kit provided by API, it’s probably lower quality than the one you buy for $40 because it’s given for us just being a fish store to my knowledge, or might be from the test tubes having been used like 10000 times, not sure, but regular APIs will usually test 0 for what ours shows 0.25. We all know this and just tell people there’s no issue. I have a skimmer and a return pump running, oxygen should he fine? As for these fish, it’s been almost 3 1/3 months, as for any fish, it’s been since i was like 5. Most recent edition was the firefish, I added him the day after everybody else because I didn’t want to overload the tank in one day. Everything’s been fine, had 0 deaths until now, i water change every single week on the dot. Only other thing i added was a new coral (clove polyp) and a few tiny fragzone rocks to stick the clove on and move my zoas onto. I don’t really think a coral hosted a parasite or disease that can affect fish, only other thing I can think of is me moving the rocks stirred up some bad stuff in the sand, but the test was the next morning after I had done so, so not sure.

The time to tell people 0.25 ammonia doesnt matter is when they just did an ammonia test to see what it was. Not when they have 2 dead fish or?

 

[LesPoissons]

We are reefers all over the country friend. No one is looking at what time you posted things and basing our responses on your personal stores hours, we are just givng you the advice you wanted. Buy a test today or next week or not at all- you're the only one invested in your livestock.

 

[Tuan’s Reef]

I’m sorry but the way the OP is responding to help is kinda ridiculous. What do you think killed your 2 fish ?

 

[ScottR]

I’ll just weigh in on the API ammonia kit, it’s probably the only test kits I would trust on a reef tank. It is actually quite accurate. Tests both NH3/4

 

[SinkyShippy]

Is your rock cycled? There shouldn't be any ammonia. Likely the fish died and then something chomped on it afterward.

 

[Rover]

It’s a test kit provided by API, it’s probably lower quality than the one you buy for $40 because it’s given for us just being a fish store to my knowledge, or might be from the test tubes having been used like 10000 times, not sure, but regular APIs will usually test 0 for what ours shows 0.25. We all know this and just tell people there’s no issue. I have a skimmer and a return pump running, oxygen should he fine? As for these fish, it’s been almost 3 1/3 months, as for any fish, it’s been since i was like 5. Most recent edition was the firefish, I added him the day after everybody else because I didn’t want to overload the tank in one day. Everything’s been fine, had 0 deaths until now, i water change every single week on the dot. Only other thing i added was a new coral (clove polyp) and a few tiny fragzone rocks to stick the clove on and move my zoas onto. I don’t really think a coral hosted a parasite or disease that can affect fish, only other thing I can think of is me moving the rocks stirred up some bad stuff in the sand, but the test was the next morning after I had done so, so not sure.

*squint*

You have fish dying.
You have registered ammonia in the tank.
You have a number of very knowledgeable community members chiming in that this is a viable culprit and problem.

Throw out that junk test kit. I am absolutely flabbergasted that someone who works at a store is okay with their equipment reading wrong and telling people that is normal.

I work industrial automation sales for a living; If I tried to tell one of my clients that their H2S sensor or their SO2 sensor will read 'just a little bit of deadly gas, don't worry' we would have a lawsuit.

 

[Poriferabob]

Just my 2 cents. No telling what killed it. But the firefish was definitely nibbled on by some sort of crab. The way they tear at things is very tell tale and obvious. I would definitely be checking the tank at night.

 

[Dom]

Sometimes, people don't care what you think, even when they ask for your opinion. They just want you to tell them what they want to hear.

 

[mattzang]

this is give or take my experience with a lot of fish stores.. lol

".25 ammonia? no problem, you added the magic bacteria right? you're fine then"

"want a mandarin for your 24 gallon tank? yeah it's totally big enough and mature enough, here's a bottle of pods to get things going"

 

[Murica]

I brought in a purple fire fish that eventually died of (i believe this is what it was) dropsy. Then my tail spot blenny died of the same thing soon after. Basically their stomachs exploded from a bacterial infection and once it does, the bacteria can find its way to susceptible fish.

 

[beaslbob]

Why would this not be the pistol shrimp?

 

[MnFish1]

Why would this not be the pistol shrimp?

It could be - but wouldn't you think the shrimp would then eat the fish - not just take a bite out?

 

[laverda]

What fish store do you work at? I am sure a lot of people here will want to stay far from it!

 

[TheGreatWave]

I'm really surprised a LFS doesn't have a good test kit, but then again I'm not. Zinger.

I have the Seachem kit which measures free and total ammonia. At the time I think it was the only kit that does this and essentially the best on the market. It's not something "fun" to buy but something all should have on hand even if you don't use it, because when all is well you don't use them.

This kit has the ability to read down to less than 0.02 (Box specs 0.05) if you don't mind waiting a little longer for a result. This could be useful for those that want to actually monitor the rise of ammonia as opposed to a coarse A/B test of a cheaper kit.

I'm not sure when this kit expires, however it says its good for 75 tests but I think that's just limited to the reagent they give you which is only needed for total ammonia. The free ammonia which I think is the one to worry about doesn't need reagent, just the disk and tank water. So maybe the disks are good for much more then 75 tests, because they don't mention how often you can use them or how many you get. I think there is 4 or 5. If you used one disk 75 times you would still have the other disks. I'm sure this is good value when you price it against other kits per test. The testing disks come in a little jar with some sort of a salt that regenerates them, so I suppose at some point that will all dissolve.

That being said I'm not against a cheaper kit as long as the expiry is good and is intended for saltwater. In theory most of us are just looking for evidence of ammonia, not a number anyway. I do however have much more confidence using this kit then the others, as it has the ability to measure low, what I assume to be non-toxic levels of ammonia. This lets you catch things early or perhaps even save unnecessary water changes in certain situations.

 

[MnFish1]

One thing for the OP to have said which would have been helpful is how big the 'very large tiger pistol shrimp is'. that said - they are supposed to be peaceful - and get to about 2.5-3 inches in size.