A rescue? NOOOO........!

[jjohnwm]

Jeez a 4 ft freeze is crazy. I don’t mind cold but that seems a bit much. Was 4 feet the frost line? How deep would you have had to go for it not to freeze all the way down?

jjohnwm do you reckon when my pond is done I should give one a whirl? They seem kinda cool but I js don’t want it to outgrow my pond.

Four or five feet of ice is just another typical winter for us as well. People drive their trucks out onto the ice...towing house trailers!...for four months each winter.

Lol, I'm the last guy to ask about these fish. I'd never even seen one "on the hoof" until these two showed up in the net a couple weeks ago. But if they get even close to their potential size in your pond, it would still eventually be way too small for one, IMHO. Aside from size, the gaudy-looking pattern is ideal for camouflage when viewed from above. You'd rarely even see the thing.

I must admit, though, that seeing a big pointy dorsal fin sticking a foot or so out of the water in a backyard pond would have a certain cool factor...

 

[Americancichlidsaredabest]

Yeah them getting to big would be my biggest concern. I’ve seen a lot of conflicting info on it tho like some sites say 2 feet full grown while others are closer to 5 I’ve heard. Anybody have any confirmed adult sizes?

 

[jjohnwm]

I've never worried too much about the "maximum" sizes listed for various fish. Those exceptional specimens are very old; growth slows down to a crawl at a certain point but never really stops completely, so any individual fish that beats the odds and lives to a ripe old age will attain unusually large size. You are very unlikely to ever see or come across a specimen that's near that maximum; it's a bit like making sure all the doors in your home are 8-feet tall to accommodate that tiny fraction of humanity that grows to be 7'6" tall.

But this species doesn't need to be old to be pretty big. There are any number of pictures easily found on the internet of specimens that are far, far larger than merely 2 feet. They aren't exceptional, they're simply the norm.

I've never subscribed to the commonly quoted ideas that a tank or pond needs to be X-times the size of the fish in length and Y-times that size in width. When we get to the point where we start to take measurements to make sure the fish can turn around in its enclosure, where it spends its entire life...well, IMHO, that's not only cruel and improper care, but...what pleasure can there be in seeing something forced to live like that?

 

[kendragon]

I have personal experience of raising them from a few inches to 24".

Things to consider are my location and environment.
I'm in Southern California where the climate is very mild. Also, I keep them in outside ponds with lots of algae.

This hobby to me is still relatively young which leaves a lot of opportunity for people to give it a go and show what they can do. If there's a will, there's a way. Make fish keeping great again.

 

[jjohnwm]

Seems like just yesterday that I brought the Hi-Fin home, but it's been over a month. First, the Bad: the fish is just as skittish and nervous as when I first introduced it to the tank. It's in a 120-gallon with only three smaller female Green Swordtails, and of course some snails and shrimp; lots of driftwood, floating plants, leaf litter on the bottom, and now a healthy growth of hair algae as well (which the fish does not eat). Walking across the room in front of the tank still has the fish darting behind the driftwood and sulking for a bit. Nervous fish like this are IMHO always more susceptible to disease; I'd be much happier if the thing started to calm down, perhaps even recognize me as a food source, but no such luck so far.

The Good: the Sucker is looking IMHO better and better as time passes; it may even have grown some tiny amount, judging from the proportionate size of the head and eye compared to the rest of its body. It spends a great deal of time working over the surface of the driftwood, the clay-tile bottom and even the walls of the tank, apparently scarfing up algae and/or biofilm. Better still, the introduction of frozen brine shrimp or bloodworms has it immediately hunting around for the source of the enticing aroma, and when it eventually finds the stuff...which tends to take some time...it now eats quite enthusiastically. Sadly, I need to be overly generous with feeding because the Swordtails need to be satiated to keep them from eating all the food before the Sucker finds it. I also find I have more success with dropping in a frozen chunk and letting the juice carry the scent everywhere; normally I thaw frozen foods in a glass and then decant 95% of the water to get rid of that source of waste, but doing that makes him even slower to locate the food. I'm doing two water changes weekly, each about 75-80%; I normally do more per change, but the fish is already nervous enough without adding to his fear by dropping the water level down too low.

The fish is obviously not blind; it reacts immediately to even relatively small motions on my part by running and hiding. But when it's searching for food it seems to go entirely by scent, never locating and approaching food items by sight.

So...I'm still not comfortable with his progress, but it is trending in a positive direction. I'm seeing the first batch of tiny shrimplets appearing all over the tank, and I'm curious if he's eating any. I also try some Northfin Bug Pro sinking pellets occasionally, but can't guarantee he's actually accepted that yet.

Lousy pic:

 

[jjohnwm]

Update on the Hi-Fin Shark; it's still alive and still making me feel like it's really going to be a PITA to keep it that way.

The fish is now a good eater, but very slow...I'm talking glacially slow. It's spent the almost three months since I brought it home in a 120gallon tank which it shares only with a couple of female Green Swordtails and a surprise pair of Gymnogeophagus rhabdotus that must have been accidentally introduced with the big handful of hair algae and detritus that I originally placed into the tank when I first got the fish. This tank was already very established, but all of its inhabitants had been placed outdoors for the summer so it seemed perfect for the Hi-Fin.

The fish isn't picky about food; it eats frozen brine shrimp, frozen bloodworms, freeze-dried tubifex, assorted flake foods and pellets...really, just about anything offered. But it takes forever, just as described in the thread by thebiggerthebetter in which Viktor mentions that what a carp would eat in a couple minutes takes the Hi-Fin hours. A particular favourite seems to be Bug Bite pellets. I'll toss them in, they sink to the bottom, and the fish responds almost immediately as it scents them. He'll then cruise around in a very leisurely fashion, passing close by the food without seeming to notice it, but obviously intrigued and searching. When he finally stumbles upon it...that's the best way to describe it...he quickly hoovers up a single pellet and chews and plays with it and mouths it and worries it...and then spits it out and grabs it again and repeats the whole rigamarole...and finally the pellet disappears and he begins the routine with another. It's absolutely the most frustrating feeding behaviour I've experienced. For crying out loud, just eat the dang thing!

The rhabdotus and swordtails are an almost insurmountable competitive obstacle for the Hi-Fin. I definitely need to overfeed them to get any chow into him. The rhabdotus have grown from about 1/4-inch to well over an inch since moving in, and the swordtails are full adults. I have no idea where I will put the Hi-Fin in a few weeks when I move my outdoor fish back inside for the winter. Any one of my tanks will present a challenge for him at feeding time, everybody eats far too fast for him to compete.

I originally thought he would be big enough to move in with the remaining goldies (lost a bunch to a heron recently, but still have over a dozen) and the adult rhabdotus in the 360, but there's no way that will work. He'd starve...or the others would be morbidly obese...or both.

The Hi-Fin has not grown a great deal, still probably just under 3 inches (started out around 2 inches). The growth that is mentioned by Viktor and also by kendragon has not happened for me. But, he looks good, never skinny, noticeable tummy bulges after feeding. He spends a great deal of time working over the surface of the driftwood in the tank; he seems to be eating the green hard algae that is typically found on the glass, but careful and prolonged observation has never revealed him to be eating hair algae. His tank is one from which I periodically must remove handfuls of the stuff; with fish that are actually eating it, like Jordanella flagfish or Goodeids, I am constantly throwing hair algae in to replace it as it is consumed.

The Hi-Fin scours all surfaces of the driftwood, often swimming upside-down to work on the underside of it. Based upon how little of it I see, I think he may be eating Black Beard algae as well, not sure.

Water temp in the basement tank has not exceeded 65F all summer, will drop down to 60F and less during winter. I suspect he will be housed in a fry grow-out tank, likely either with rhabdotus cichlids, Oryzias ricefish or maybe just with the swordtails. It's pretty obvious that he is one of those uncommon species that grows large but can be kept with the smallest of tankmates without worrying about predation. Hell, he has a hard time predating on a stationary pellet on the bottom; live targets have nothing to worry about.

Suddenly having problems with pics, will try later again.