What happened to our Lionfish (not eating)

[Oceans n Indy]

Looking for any thoughts as why our lion-fish suddenly quit eating 3 weeks ago and has consequently passed on. Nothing in the tank set up was changed , I just noticed a few weeks ago that when I was feeding the tank , he was not interested in eating . I tried buying a fresh bag of krill and also bought some live feeder fish to try to entice him to eat. At that time the nitrates were a little high , and the salinity was also , Due to me being out of town when I normally would have done my water change. I changed out 15g of the 55g tank and evened out the salinity to 1.025 where my tank has normally running at. After another week of him not eating, I changed out another 15g water to help keep the nitrate level going back down, and bought some silver-sides to try to entice him to eat, but to no avail , and after returning from work yesterday I found him passed on . So I'm looking for a little help in determining what might have made him meet his demise .

Other information from questions for posting on sick fish: I have had the lion fish for about a year now. The tank mates are a snowflake eel, undulated trigger , and a panther grouper . The lion fish normally ate pretty good at each feeding , about every 3-4 days consisting of frozen krill. The parameters around the time that I noticed him not eating were PH-8.0 Nitrite 0 , nitrate 60-80 range and SPG1.028 using the API saltwater test kit(drops in test tub). I saw no physical signs of disease until maybe the last week when his pectoral fins were noticeably darker in color. he never showed any signs of flashing and normally would hover over around his normal 2 or 3 spots in the tank. He was drip acclimated a year ago when I got him, and was never qt at any time. The tank is 55g using a fluval306 canister filter along with live sand and 55lbs of live rock, and no additives or any kind of meds have ever been introduced into the tank.

I posted picts of the lion fish after I pulled him from the tank to see if anyone see's something that stands out physically.

 

[ImACoolguy]

Feeders and sometimes frozen can carry parasites.

Possible one of his meals introduced a parasite causing his lack of appetite?


Caleb

 

[Andy Sager]

Krill is not as nutritious for these fish as fish are. So my first 2 thoughts are 1- that the food ( or lack of variety of foods) may have finally caught up with him and/or 2- some form of upset stomach or internal disease ( since he didn't show external symptoms) is at play here which is why, when not treated, he finally succumbed.
My last thought is that the nitrate level may have gotten high enough to bother the fish to the point that he became ill. Not that it's so high that it's catastrophic to all but certain fish react differently to different levels of nitrates and he may have just been one of them that 60-80 ppm didn't agree with him? The rise then fall in salinity shouldn't have been enough to cause any damage to the fish so I rule that out. Since you've had the fish for over a year, old disease or acclimation method is not really part of this issue anymore. If those were at play, it would have happened a loooooooong time ago.
In the future, if you do decide to get another lionfish, make sure you give a varied diet containing more types of foods that offer different levels of protein, greens, and vitamins.


Hope this helps.

 

[stingrays4]

Hi a daft question but was his belly region sunk in? Or swollen?
I recently read that fish only marines prefer the salinity much lower? I do not keep marines anymore so this is only from what I have read.

 

[Andy Sager]

Hi a daft question but was his belly region sunk in? Or swollen?
I recently read that fish only marines prefer the salinity much lower? I do not keep marines anymore so this is only from what I have read.

Based on the pictures, the belly looks shrunken in which would be typical of a fish not eating for 3 weeks.
As for the lower salinity, I don't think that it's a "preferred " method by the fish as normal salinity where most of our aquarium fish are collected is near 10.22- 10.25 +/- depending on temp & rainfall, etc( the Red Sea is even higher) but keeping the fish in the lower salinity was found to help reduce many parasitic diseases as they don't like the lower salinities. Considering the fact that the fish seem to handle the lower salinity without issue, why not try to help curb some diseases with the lower level in the tanks?

 

[PB_Smith]

The salinity at 1.028 is on the verge of being a problem for the fish if long term. If you have no coral then it is fine to keep it around 1.022-1.023. Along with the benefit of less aggressive parasite issues, the lower salinity makes it easier for the fish to do the whole osmotic balancing act. The higher the salinity the harder their kidneys have to work, and long term it can be problematic.
Having said all that, unless the salinity was that high for a very extended period of time, I doubt it was the cause, and for sure it wasn't because you lowered it too fast otherwise the effects would have been noticed within minutes, not a week later.

I also have doubts about the nitrate level being the culprit. 80 ppm is not drastically high at all for fish, inverts and coral yes, fish, negligible impact.

One thing to consider is the trigger. Were they roughly the same size or trigger smaller a years ago?
Is the trigger now the same size or bigger than the lion was?
Undulated triggers are one of the meanest and territorial of the family and I would not be at all surprised if as any size differences became less, that the trigger began exerting it's dominance and may have been stressing the lion and keeping it "under it's thumb" so to speak.
I've seen it happen before, where a dominant fish won't kill the others, but it won't allow them to eat or roam the tank freely until they die from stress.

The few undulated triggers I have had experience with all ended up as the only critter in the tank.

and as a side note, feeding fresh water feeders; guppies, goldfish, to salt water fish presents very, very little possibility of introducing parasites. But do not use any live saltwater fish as feeders because they will be almost certain to have something undesirable on/in them.