Crenuchus spilurus (Sailfin Tetra)

Soooo.....a thread on these fantastic fish.

Some people may wonder why on earth would I rave about these fish.....well, not even these videos can show you how interesting these mini Hoplia-look-alikes are.

Although these fish are shy, peaceful, can be difficult to feed, and require good water. they are great community fish (so long as other fish are not too boisterous or too small to easily fit in the Sailfin's mouth).

Not easy to get a video of these as the fish are kept in a clay/peat water....but by virtue of a new headlamp, I have some videos.

The first is just a nice Intro video.
The second is the bizarre way they attack flake food on the surface.





I'll do some more vids of them feeding in different styles.

It has been many years since I last bred these, so I am hoping to have a video of the cave-spawning (if I manage to tempt them to breed).

Please add to this thread anyone who keeps these.

Ian

Its really interesting to watch em feed. Love how they shoot up vertically to the surface!!

Sometimes they completely clear the surface and the whole body is out of the water.....and that is just when feeding on floating flake food. It's actually a bit mad to see a fish be so 'eager' about dried flake.
Especially, when these can be real problem fish to feed.

You can see a very ancient fish behaviour.

They also line up when I arrive in the room in the morning.

ian

Cool vids Ian thanks for posting


Mark

beautiful and rarely seen fish Ian, looking very healthy and active, they are a credit to you, how do you tempt these to spawn, and would love to see a video of that happening

In many respects, Sheag, part of the credit would have to go to the LFS for securing some really good specimens in the first place.........and also to them for not stressing them out whilst being caught.

Often the stocks are rubbish, and these fish do not do well in coming back into good condition.

The way that I settle these fish in is by emptying the fish and water from the LFS into an empty tank then gradually air-line siphoning a small amount of water from, usually, a Discus tank (where I would have a sponge filter already working away for inclusion...and that sponge filter being dosed with bacteria).

Then fresh water is added slowly over the course of a day or so. I do not use RO water by the way.

Also in the water peat is added directly to the water, and I add clays to help lock-up stray ammonia during the initial settling in period.

Really, it is quite important to make sure that the settling-in period has no plips in it as you don't want them to go off the food.

OK...so for how I used to get these to breed.....simulate their seasonal changes.

In this batch I bought 4:3 males:females, but that is to give me a 1:3 male:female ratio in the end.
3 of the males will be removed when one shows his dominance.

The water is kept in good condition (with a low conductivity, peaty, and soft) for a long period with very regular partial water changes, then there will be a period of letting the tank 'slip' a little:
water changes will be reduced, pH will rise slightly, conductivity will rise slightly, and the lid of the tank will be removed (making sure the fish can't leap out). Feeding will be reduced somewhat, and the filter speed will be turned down.

Have bogwood etc that will be ultimately out of the water and thus effectively reducing the width of the water as the water level lowers....simulates narrowing stream banks.

Now, this is slightly dangerous for a delicate fish such as these....so it needs to be done with care.
Having modern zeolite resins around (such as ammonia absorbing clays or JBLNitraEX is a good idea).

Then, do a largish water change......add in fresh water, and slowly reduce the pH and conductivity, add more peat and ammonia adsorbing clays (this will also increase the 'mulm' on the bottom of the tank....that is what you want).

Increase the flow of the filters, and have some water trickling in from above.

Add the lid, and increase the air pressure. Feed plenty of frozen food (bloodworm).

.....and keep the fingers crossed. These are not always a 100% guarantee to breed.

Now, they sometimes may spawn on the odd occasion in the tank anyway, but that is leaving things to chance a bit too much.

Ian

Very interesting videos and fish, thank you for posting Ian!

I love this part of fish keeping where you learn about a unique species seldom seen.
Many times these oddballs are so underestimated and at the same time so interesting.

Melander

Very nice indeed Ian.


Kev.

Well after working with these fish for about a month I have my first spawn and seems to be a fairly decent size. They are right at the back do a decent photo is near impossible but you can just make out the eggs in the left of the cave:-)

Jamie

well done Jamie you know who to keep in mind if you decide to sell some on later

Keep the fingers crossed.
You'll know in about 2 days if they spawning is successful or not.

ian

sheag35 wrote:

well done Jamie you know who to keep in mind if you decide to sell some on later

Shiver me timbers, me matey Sheamus "the piscatorial Pirate" strikes again...........

cool little fish and an interesting post cheers ian

Eggs have hatched and looking good so far

well done throw up a vid or some pictures never seen fry of these

sheag35 wrote:

well done throw up a vid or some pictures never seen fry of these

Few people have.

Videos? Pictures? come on then.

ian