Dojo Loach Spawning

[Aozora]

Good afternoon!

At noon today, I noticed that our dojo loaches were behaving oddly. After a few moments of observation, I realized that they were spawning!

Supposedly, dojo loaches don't spawn easily in aquaria. I'll list here the conditions that led to the spawn, in case anyone is curious, and later on I have a few questions that I hope someone can help with.

Two weeks ago today, we moved the 44-gallon, completely emptying it and setting it up again. At the same time, we merged all the dojos. The temperature of the water is at 73 degrees, which was cooler than the females were used to. The pH is at 6.5, the NitrIte is 0 ppm, NitrAte is ~30 ppm, and the phosphate level is somewhat high at 5 ppm. We've been feeding them bloodworms and Hikari meat pellets as a matter of course.

The male and the female separated off the bottom of the tank and swam about at mid- to high- levels in the water column. The male swam with his mouth and barbels all but touching the female, right behind her gill cover or slightly farther back, by her pectoral fins. They would swim like this for about ten seconds, when the male would wrap himself around her pelvic fin region, and she would scatter about 20 eggs in a burst. The eggs adhere to any surface, especially to the small leaves of the artificial plants. The breeding pair would go back to the bottom of the tank, then repeat the behavior about thirty seconds to a minute later. I'm not sure exactly when they started, but they continued this spawning behavior for at least twenty minutes. The other loaches in the tank became agitated during the whole process, especially the males. One or two of the other males would attempt to rise with the female, but they would give up before more than three seconds passed.

The female and male that spawned were the oldest fish in the tank. Both are a little over two years old. The male has natural dojo loach coloration, while the female is a so-called "golden" dojo.

This leads me to my several questions. First and foremost, does anyone have any experience with dojo loach fry? We are setting up a 20-gallon fry tank, where we will transfer the plants containing the eggs. We've got a sponge filter and will attempt to feed the newly-hatched loaches baby brine shrimp. As a backup, we have Hikari Firstbites fish food.

Secondly, does anyone know anything about dojo loach genetics? I would assume that the natural coloration would win out over the golden coloration, but I'm curious as to what the fry might look like.

Thank you for any help you can give!

[Mollielover]

Hi there!  what an amazing thing you have had happen here, of all my years on this fish site this is the first time I have heard of anyone spawning their dojo loaches.  Congratulations, keep good records such as what you provided here.  What kind of decor do you have in the tank? Plants? substrate?  Frankly I would have thought that a 44 gallon would have been too small for them as the dojo loaches I have tried to keep have all jumped ship out of my 80 gallon.  I swear they found the smallest hole and jumped!   I would love to hear how this turns out for you.

As far as the genetics go, it would be my guess that you are going to have some of each but that is just my best guess.  Do you have any clue what you might feed these guys when they hatch?  I think I would try to get some microworms or something very small like that.  the fry may be big enough to take bbs.   Golden pearls may be another option.   

Again good luck and please do keep us updated! How exciting!

[Aiptasia]

Pretty cool stuff. Dojo loaches aren't known to spawn in home aquaria. First i've heard of it. Would you be interested in submitting an article or perhaps recording one for our upcoming podcast?

[Aozora]

I'd love to do an article, but it was a pure accident so I don't know how much I can say with authority. Might want to wait until the eggs hatch and the babies start growing. I'm hoping they didn't get damaged by their move into the 20-gallon. It already looks like some of them are developing, though! We matched pH and temperature, and now we can just wait and hope they'll hatch. I didn't want to put substrate in the tank, for fear of how little the fry will be.

I really have no idea what to feed the lil' guys once they hatch--that's why I came on the forums. I assume baby brine shrimp will work, given that they seem to be a good food for most if not all baby fish. The eggs are TINY in comparison to a mature loach, but really they're about the same size as betta eggs.

As to the tank they were in (second picture), we had pea-sized natural-colored gravel substrate. It's not fine enough for the loaches to dig, but they do manage to dig in under the decorations and plants. We use two filters--a Fluval 305 canister capable of handling 70 gallons, and a TopFin 40 power filter capable of handling 40 gallons. There are several decorations, and lots of artificial plants. Right now, it's barren because I had to remove the plants that were holding the eggs. Unfortunately, the only camera I have is the one on my phone, so quality is not great.

The top photo is a picture of the plants with eggs. They're very hard to see--look on the broad part of the leaves. There are a lot more eggs there than just those!

Second picture is the 44-gallon the fish are in. The big one in the middle is Mom. (Her name is Aramis--named her before we figured out she was a she.) Dad (Longfellow) was swimming around, but he didn't hold still long enough for a picture.

[Mollielover]

Wow, thanks for the pictures. if the eggs are as small as betta eggs then you can bet the fry are going to be tiny, you might get away with feeding bbs, but i'd still try to get some microworms if you can.  you might find someone here who has a culture started that they can send you. 

[Aiptasia]

You might also try some of the smallest micron size of golden pearls. Ken's fish sells it. That, or culture some small rotifers or just plain old infusoria (green algae water) for the fry to nibble on after they've absorbed their yolk sacs. Check our articles section for more on live foods for fry in the articles link in the upper left of any petfish forum page.

[Aozora]

Thank you for your suggestions!

I don't know if we'll have time to culture infusoria. I'm willing to give it a chance, but what little is known about dojo loach breeding states that eggs hatch in 3-5 days. I have no idea if that will be enough to make a stable culture!

I'll give the Ken's Golden Pearls a try, hopefully we can get them delivered in time as well. I'm perfectly willing to toss anything I can at them, to see what they'll eat. Thankfully, the one account I did read about dojo fry says that they grow FAST. It makes sense, since the eggs are developing so quickly. The center of each previously-clear egg is white already.

[Mollielover]

I'm finding this so facinating!  Good luck can't wait to hear more.

[Aozora]

It's now been approximately 24 hours since the spawn.

Mom and Dad are fully recovered. Mom actually looked squeezed, like a tube of toothpaste, just past her ventral area on both sides of her body during the spawning. The squeezed marks are gone now, and she just looks a little skinnier than usual. Dad is pretty clearly proud of himself--he's remained the darkest I've seen him ever since the spawn! I was worried I'd have to separate them after spawning, given that Dad can be a bit pushy to the other loaches, but it appears that the dojo's good nature is proven yet again.

I wish I had a decent camera; vaguely fish-shaped forms are visible within the eggs! It looks as if the move to the fry tank didn't hurt them at all. One or two eggs have not developed, but that's fine considering how many were laid in total.

Now it's just the waiting game til the fry hatch!

[Aozora]

... Crap!

I guess what's known about dojo loach hatching is wrong. Just checked, and they're already hatching. Looks like precisely 36 hours from when we saw the parents spawning. We're not really prepared to feed them yet--stuff still in the mail. Gonna try to put some dissolved egg yolk in there so they have something to eat when the remains of their yolk sac is gone.

They're so tiny, and translucent. About the size of a betta fry, but much, MUCH more active.

Help! Hahaha