Rice fish breeding set up

[Luca]

I am setting up a 50 gallon stock tub to breed rice fish. I have never done it before but plan on putting in spawning mops and changing them out every other day. I will put the used one in a breeder box in the tank until I see free swimmers then dump the contents into the tank. How does this approach sound? Also should I start with 8 or 16? Price is not that big of deal so I think I’ll go with 16. Also should I add other plants to tub or should I just keep it to spawning mops so they don’t spawn on plants? I also have cherry shrimp I was thinking of putting in but don’t want to put them in without plants but I don’t know. Please if you have ideas give me one on this set up. The tub is like 40 inch by 18 by 18 ish *not exact messurements just off top of my head* 

[Bsquared]

If you can afford the 16 off the bat, I’d say go for it! I have had the most success with no plants in the tub with them just a few spawning mops if breeding is the goal. I leave the mops in with the adults for 7-14 days. At day 14 eggs that were laid on the first day of the mops should be pretty close to hatching. I then take the mops and put them in a 10 gallon tank (or breeder box) and leave them for another 14-18 days. During this time you should have new fry hatching every day. Newborn fry are pretty small so I wouldn’t add them back in with the adults for at least another month if not 2 so they are large enough. I feed sera micron and baby brine shrimp 2-3 times a day. You can end up with tons of fry this way so if you want smaller numbers just pull the mops sooner than 14 days to limit egg production. Hope this helps!

[MrGibson]

Plants help a lot. Specifically fine plants near the surface. Hornwort is a great option. Be VERY mindful of floating plants covering the surface. If the water gets hot, and the surface is overrun with floating plants you have very little gas exchange happening in water that already doesn’t way to hold oxygen. I learned this the hard way this summer with medaka (also my first time breeding outside) and I got up to around 250 fry. Then my dad had an emergency with his 600 gallon reef that required me to be away for 4 days in the height of Tennessee summer heat and all but one fairly mature fry died. I only lost one adult because medaka are so tough, but the fry aren’t so resilient.
 

I think my biggest issues here were not staying on top of the the floaters, tub placement (got full sun in the middle of the day), and my tub being relatively small. I was working with a 27 gallon tub and that volume of water got hot quick. I found though I’d get a very distinct thermocline about 5-6 inches below the surface where the water was much much cooler and didn’t feel like bath water. The adults were fine down there but I don’t know if the same would work for fry. I’ve now got them back inside and finally just last week got fry again. Not many fry right now but I’ll get there. 

If you’re trying to colony spawn and have the babies with the parents heavily planted in the way, but if you want them to lay on mops I’d use riparian plants in pots like aquapros does on YouTube. I’ve found they very preferentially lay on plants over mops if they have the option.

All in all I think you’ll probably have success. Medaka are easy to breed and the adults are the toughest fish I’ve ever worked with. I’d definitely start with the 16 fish as you’ll expand your population faster, but also have broader genetic diversity. Good luck!