Emergency

dR3ws3r · Jan 12, 2026

Hi,

I have a 155 gallon tank and all of a sudden I am seeing fish that aren't eating and a few deaths. i have done a 20% water change over the last 2 days, but things seem to be getting worse.

I do not see anything on the fish bodies that indicate an issue. No films or dots.

My Hippo tang is swimming back and forth eratically. I have lost a diamond goby and now an exquisite fire fish.

My parameters seem to be ok (Alk, mag, phos, nitrate). i did an ICP by conicidence on the 30th of december, and nothing odd was found then.

I noticed that my torch and hammers have closed up over the last 2 days.

Any advice or suggestions PLEASE!

Hairyteeth · Jan 12, 2026

People
Will ask for actual parameter numbers to start, good pictures and videos of fish under white lights to start to figure out

dR3ws3r · Jan 12, 2026

Hairyteeth said:
People
Will ask for actual parameter numbers to start, good pictures and videos of fish under white lights to start to figure out

Alk = 8
mag 1344
Cal =411
nitrate =3.0
Phos = 0.07
Ph = 8
tmp = 77.1

Nothing seems to have changed or is out of the ordinary.

I have had Dinos, and have been dosing Silicates and neo-nitro over the past 3-4 weeks, and my Dinos seem to have started to disappear.

I have been using the frozen food feeder since Christmas, so I don't think it is food.

Could it be electrical? Should I try and do a massive water change?

Hairyteeth · Jan 12, 2026

Let’s see a video of the fish behavior, and the tank,
You’d feel electrical most likely when your hands in the tank

dR3ws3r · Jan 12, 2026

Hairyteeth said:
Let’s see a video of the fish behavior, and the tank,
You’d feel electrical most likely when your hands in the tank

ok. Here are a few pics of the fire fish I found dead today

dR3ws3r · Jan 12, 2026

Video

lmfbs · Jan 12, 2026

dR3ws3r said:
Alk = 8
mag 1344
Cal =411
nitrate =3.0
Phos = 0.07
Ph = 8
tmp = 77.1

Nothing seems to have changed or is out of the ordinary.

I have had Dinos, and have been dosing Silicates and neo-nitro over the past 3-4 weeks, and my Dinos seem to have started to disappear.

I have been using the frozen food feeder since Christmas, so I don't think it is food.

Could it be electrical? Should I try and do a massive water change?

What frozen food feeder? Any chance things defrosted and refroze?

dR3ws3r · Jan 12, 2026

lmfbs said:
What frozen food feeder? Any chance things defrosted and refroze?

The new InD AF4. I don't think so. We haven't had a power outage. The food stays in a "cold" state, that is close to freezing. I haven't cleaned it out, so perhaps there is older food in there? I have a QT tank with a Blenny in it, and I give him the same food, and he seems to be fine so far.

Jay Hemdal · Jan 12, 2026

dR3ws3r said:
Video

In the video, the fish are too far away for me to count their respiration rate, are you seeing rapid breathing?

The water looks really still, did you turn pumps off for the video? Adding an air stone would never hurt.

What is the ingredient in the Neo-nitro?

dR3ws3r · Jan 12, 2026

Jay Hemdal said:
In the video, the fish are too far away for me to count their respiration rate, are you seeing rapid breathing?

The water looks really still, did you turn pumps off for the video? Adding an air stone would never hurt.

What is the ingredient in the Neo-nitro?

I do not see rapid breathing, and I did turn off the mp40s for the video. Neo Nitro is the brightwell nitrate supplement. I only add a little. The ingredients say purified water and proprietary nitrogen salts.

dR3ws3r · Jan 12, 2026

Is this a better video? It is tough to get a closeup when they keep moving.

Jay Hemdal · Jan 12, 2026

dR3ws3r said:
I do not see rapid breathing, and I did turn off the mp40s for the video. Neo Nitro is the brightwell nitrate supplement. I only add a little. The ingredients say purified water and proprietary nitrogen salts.

Thanks, I just wanted to rule some things out.

What about toxins from the Dino’s?

dR3ws3r · Jan 12, 2026

Jay Hemdal said:
Thanks, I just wanted to rule some things out.

What about toxins from the Dino’s?

I don't know. Is that possible? I have been running Activated Carbon to help with that, but I "think" I had small cell amphidinium, which is not supposed to be as toxic, although I do not know what low-medium toxic means. I have never heard of fish dying from Dinos in a reef tank, but I am not an expert.

Jay Hemdal · Jan 12, 2026

I’ll have to defer to others on that. I’ve never had Dinos in my tanks. I just see fairly common issues that seem associated with Dinos and/or their treatments.

dR3ws3r · Jan 12, 2026

Yesterday, the fire fish were hiding behind some rockwork. That is not a usual place for them. They tend to stay under the sand with the Pistol Shrimp or out in the open. Today one is just dead, and other seems to be hiding. All this is happening very suddenly. I have only had 1 fish death in over a year and that fish was (I think) blinded by something. Everything was great 3 days ago, which leads me to believe this is a water issue. I always QT fish for at least a month before putting them in, and I haven't introduced anything in probably 6-8 weeks. I have been dosing more things than normal lately to try and help with the Dinos. That includes Microbacter 7 which I have been dosing for forever, phytoplankton, silicates (to create a diatom bloom), neo nitro to try and raise my nitrates, and a little AF Life Source. The Royal Gramma seems to be swimming a little oddly now, but it is a little hard to tell. I could just be paranoid.

Any general suggestions on what to do? Major water change ... but that would be tough as I am not set up to do that. But I will try and convert my RO/DI brute can to a salt mix. I am pretty desperate, and this is all new to me, so could use any advice. I do have a QT tank but it is only 22 gallons, and putting all the fish in there would be .... difficult.

lmfbs · Jan 12, 2026

dR3ws3r said:
I don't know. Is that possible? I have been running Activated Carbon to help with that, but I "think" I had small cell amphidinium, which is not supposed to be as toxic, although I do not know what low-medium toxic means. I have never heard of fish dying from Dinos in a reef tank, but I am not an expert.

I've definitely had dinos wipe out all my snails, and I suspect they were responsible for my sand sifting goby's death.

sgdnycct · Jan 12, 2026

Kind of hard to determine what’s going on so just some ideas:

Could it be bullying? Sometimes there are few clues and they are sly enough to not do the bullying when you’re around.

Check for ammonia?

I’d cut down or eliminate any additives. This is just me personally: I don’t like additives other than basic Alk/Ca/trace. There are so many ingredients that if you are using a number of them they could interact or create high concentrations of elements. Again just me but you could try it.

Maybe take a couple of fish into QT to see how they do. If they improve it’ll point to water issue v. disease.