On occasion, upon lumbering into the fish closet, I sometimes see fish, ranging from good sized juveniles to fry, rocket to the surface of the tank, and immediately go into 'shock'; just float around more or less vertical.

Sometimes, they seem to snap out of it, though it helps to isolate them for a bit till they resume breathing.

Sometimes, not.

Doesn't seem to be particular to a tank (crowded tanks, lightly loaded), but it *does* seem to be 1 species (A. australe 'chocolate') that does this moreso than others (various nothos, other aphyosemions/fundulopanchax.)

Have others seen this? Is it diet/heredity/tank conditions? An issue of tank placement? Should I stealth-ninja my way into the fish closet (a roughly 4ft square closet with tanks stuffed in it)....

Suggestions?

Matt in the PNW, with very soft water

Funny that you should mention A. australe Matt! Years ago (before the 35 years where we have fought with liquid rock) we lived in a 4-flat with Lake Michigan water and the landlady allowed me to set up the killies in the basement (cleverly overlooking the small detail that it would be so cold down there that I would add significantly to the heat of the whole darn building while trying to keep the killies alive.)

Wandered in late one night, clicked on a ceiling light and noticed a golden flash the length of a 10-gallon tank and a sickening tdionk as a female golden australe fatally brained herself on the end of her quarters. I'd read about "crazyman's disease" (or acidosis) where an aquarium's pH plunges (usually in response to heavy feeding of growing killies) and redoubled my efforts at partial water changes. And these days changing water advice is along the line of "do what I say not ..."

However, the real reason for that mishap may have been the startlement or shock caused by the sudden flashing on of an overhead light in a dark room. Have since sought to avoid such unnecessary fish deaths by leave a "moon" on over green water or Daphnia tanks on the floor. The added benefit is one doesn't get clobbered so often slipping in to check something in the dark.

In the morning one timer (in a corner) goes on before the others. The gradually turning on and off of lights sort of resembles the cycle of the day (but longer.) And light leaks in the windows after a point.

When getting up early to bag something for a fish show (there never seems to be time enough the evening before - gotta turn off the phone) a light in the next room is turned on while other necessities (like coffee) are attended to. Then a light in the less crowded part of the fish room is put on.

It would be nice if fluorescent lights could go on a rheostat.

Are the lights off in your closet before you open the door? What ways might a fish be startled when the door opens? How then of course, could that be avoided?

If the closet is dark or dim, could you install a Christmas tree type light (3 watts?) near the floor of your killie closet? How about a small LED light there? Or perhaps even an arrangement where you could turn on that light via a switch outside of the room? Maybe turn a rheostat on gradually?

I've seen a Betta closet and a killie closet. Both were ingenious masterpieces of planning. I recall airlines in both and in one gloriously healthy Java ferns. In our town (planned and built shortly after World War II - sometimes with odd surplus parts) homes were built on the assumption that no one would ever need more than two electrical outlets in a room. I think another assumption was that since people only had a couple changes of clothing each, why build many or large closets? Closets here may be the most coveted part of the house. We will be converting the bedroom of a departed (now adult) child into a walk-in closet. I would recommend keeping fish there at my peril!

Maybe nothing is of use here. Hope there was grist for the mill. All the best!

Sounds like a light reflex.

Of course, it does beg the question what you are wearing when you open the closet?;)

Cheers buddy!
Markus

I have had a similar experience with Gardneri in a 20gal long grow-out tank which I haven’t figured out either. I tried the most obvious things first, (although I didn’t think to try a different outfit).

I rigged up a light in the opposite corner of the room and turned that on first, then turned on the room lights, then finally turned on the light over the tank. In each case the fish went berserk when each light was turned on with a fresh panic when added lights went on.

With the tank light on them for hours they stayed hidden until I removed the light. They wouldn’t even eat white worms. Not good for a grow-out tank.

I packed the tank with mops but that didn’t help much. I put old sponges; driftwood etc. in the tank but it didn’t help except they didn’t go bonk on the glass anyway.

I then put a net full of Endlers in with them and all that accomplished was panicking the Endlers also.

I thought it was due to overcrowding so I moved some to a community tank and the ones I moved starting acting normally. The ones in the original tank still panicked when the light was turned on.

I have since moved the remaining Gardneri into the community tank and they seem normal. The tank light going on in the morning bothers them less than the other fish.

Here are some of my thoughts on this;

Is it “fear” scents that the fish give out that signals all the fish to hide? Would the tank have that smell for a long time later thus magnifying the panic?

Or could it be a learned response that I changed by moving the fish to new quarters?

It doesn't sound like this is a practical solution to your problem but I would be interested in finding out your solution if any.

Bob

Well, other than my Markus Brown fright mask, I don't think it's anything I'm wearing.

As far as light goes, the fish closet lights are already on when I venture into the fish closet. The tank in question has a small (15w) incandscent light in one of those 'hazardous to your health' old metaframe hoods. And, the way the closet is set up, it actually has a window in the door, which faces another outside door with a window in it, so there's a little bit of daylight that gets in. Of course, with the 7 months of cloudy weather and the northerly location of the Puget Sound, they don't get a *lot* of light, but hopefully enough to give them a little diurnal cycle.

It *could* be acidosis, yet, same tank, less filtration, more different fish (scheeli) a month or two ago and never had this problem. Just with a lighter load of australe.

I wonder if its not simply due to how the fish were reared. Scheeli are scooped from adult tanks when it looks crowded (which is often), to other grow out tanks. Never a 'shock' problem. Australe, are raised from carefully picked eggs, reared in cleanish plastic containers with regular water changes, a thick clump of java moss, fed the tastiest and scarcest live foods (daphnia, occasionally cyclops from the outside buckets, the tiniest mosquito larvae I can nerdily eyedropper out of containers, lots of fresh bbs carefully sifted for unwanted eggs, grindals, small blackworms...) It could simply be spite, the fish you really want, are touchy, the ones you can't give away, breed like fleas.


I will try the led/nighlight thing, to see if it helps. I also wonder if its not something in the old metal framed tank, though I've seen the shock syndrome in the Australe breeder's 5.5 all-glass, too, though fewer fry are in that tank.

Thanks for the suggestions.

-Matt

F right syndrome. Seems to sometimes be associated with CO2 levels or ammonia levels. Usually alleviated by water changes, even if you don't know the causes.

A reference is JAKA July/August 1997 Volume 30, No. 4

Sudden changes from lighted to lights out can panic fish. This is far from being limited to just Killiefish.
As hard as it may be to do the more time you can spend working on and around your fish the less problems your fish will have with panic attacks.
I have been keeping and breeding Killiefish and Discus for about aslong as each each other and that is some 40 plus years. Discus, especially wild Heckel Discus are very prone to panic attacks. What sets them off is hard to pin down because they may be perfectly calm during the routine water changes and yet just the motion s of putting on a jacket from across the room can send them crashing into the sides and wood furnishings but the actual time spent working around them is directly related to whether or not they panic.
So that is where I would begin.
Having a transitional dim light come on and switch off can also reduce this flight/fright response.

One similar mystery I have experienced is during growing out fry the fish would be calm for months and just about the time they begin to color up I have had whole tankfuls of fish decide one night to all jump out like so many lemmings to their deaths through the smallest of openings.
I think at the stage many species of killies are beginning to mature they may jump out a lot to disperse to adjacent puddles. I have seen my various Scritoaphyosemion species be espescially prone to do this but in a fish room they don't often land in another body of water.

Polluted water as a cause is much further down on my list of possible causes but it too can cause the behavior you are experiencing.
It may take some combination of thing to reduce this problem. Having a nearly complete cover of a floatng plant like Ceratophyllum(Hornwort), Water Sprite or Riccia may also help reduce the panic response.
I do believe in the hypothesis that once fish panic they do release a "fear pheroomone" which over rides all their common sense and can cause the flight response.

One other factor that can cause fish to jump is electrical current. I had an experience this Summer with a submersible pump I was going to use to empty an in ground pond. All the dace jumped out as soon as i plugged it in. A different pump with a grounding plug had no effect. Many years ago I had a tank of Aphyosemion bitaeniatum die suddenly. Later, when cleaning the tank, I received a shock when I put my hand in the water. I think it was a faulty heater.

The suggestion that this is partially a response to reaching maturity is pretty interesting one. All the fish in question (most have expired by now), were just starting to reach maturity.

I tested the water - no metabolites at all save a little nitrate. The tank in question had held a very large number of immature Fp. scheeli fry until recently, so the filters were very mature and the water clean. Nothing electrical in the tank, just a box and a sponge filter.

The other suggestion about getting the fish used to being in a different tank, with a different view of human activity is also pretty interesting. Prior to moving to this tank, the fish were reared in opaque plastic containers and the change to a glass tank could have, I dunno, caused 'killi agoraphobia'

Thanks for the suggestions. I'll try rearing the next bunch differently and see what the effects are. FWIW, Fp. scheeli (raised up with parents in adjacent tanks) transition fine to this tank