Zebra Danios & Spawning

[yashinfan]

I have four danios now, two of each sex. When I put the first couple into the tank, about four hours later they started chasing eachother and the guy tried to wrap himself around the girl. I was just wondering if that was the act of mating, since I know some fish do it differently than others. Those two are very very small so I didn't think they could even spawn yet? Later I saw some tiny lil white specks come out around my female so now I'm really wondering- Did they spawn ALREADY?? lol, that would be quite impressive. If they did in fact spawn, do you think there's a chance that any would live because I don't have anything to protect them in that tank (ie- no marbles, no real plants)?? Today I'm going to pick up a 10 gallon tank from my friend and I am either going to use that for guppies or for a breeding tank. Do you think a breeding tank is necessary? Will the fry be able to live in the 23 gallon tank?? I'm so confused now :)

[OrionGirl]

Danios are the aquatic equivalent of bunnies--if you take the right precautions. Eggs are fertilized externally, so the wrapping you saw was probably courtship or such. Females drop eggs on the substrate, and males follow behind fertilizing them. Without large substrate that allows the eggs to fall down where the adults cannot reach, they will be eaten. My LFs (who I do trust) offered the following method: Add fish to tank with marble substrate. Leave in tank 3-4 days. Remove adults. Begin feeding BBS on 5-6 day (tank at 78F). He calls danios add water and grow fish.

[yashinfan]

Do you know how big they would have to be before they could spawn? My little ones are about 2/3 the size of my biggest ones. So pretty small. Alright, I'll take your advice OrionGirl and invest in a breeding tank for them, I'm going to buy a sponge filter for it too as that seems to be the most highly recommended filter for a breeding tank. Do you think a 10 gallon tank is a good size for a breeding tank?
Thanks :)

[OrionGirl]

Should be fine. I am not sure, but with many fish, they are sexually mature within about 6 months. Not to say they will successfully spawn and fertilize, but they will go through the motions. Every healthy danio tank I've ever seen in the store had fish spawning, even though the fish were not adults.

[yashinfan]

How do I know how old my fish are if I bought them from a LFS? The bigger ones look like decent candidates to successfully spawn but the smaller ones look like they are still growing. *sigh* If only fish could talk, it would make things a lot easier. lol :)

[OrionGirl]

Trial and error. Sorry--there's not fish fertility tests for danios. However, these fish are used in labs for experiments because they are so quickly and easily bred, so I would imagine that most trios should result in fry.

[yashinfan]

My plan is to have 10 danios in total, I'm going to try and get some more bigger ones. I want to have 4 females and 6 males, does this sound like a good ratio? I was told that they should be allowed two weeks to settle into their new tank before I try to start breeding them in a seprate breeding tank, does this sound like good advice, or is it too cautious? Do I need to seperate males and females? Every where gives different advice and I know that people on this forum are generally experts so I hope you'll help :)

[OrionGirl]

I'd reverse the gender ratio--you want more girls, not more boys. Any given female can produce a finite supply of eggs, while any given male can fertilize the clutches from many females. I'd probably go with 7 females and 3 males, even--this will reduce the amount of attention any given female receives at any time. I wouldn't separate the fish, just be sure to remove them once they've spawned. They will dine on the eggs if they can.

[yashinfan]

Wow, thanks OrionGirl, otherwise I would have gone about this all wrong. I thought it was just for guppies that you had two girls for every guy. Thanks so much for your help :) Do you have an idea about when I could get more fish? ..since I added four yesterday and they are doing great.

Thanks so much again! :)

[OrionGirl]

If everything is still stable tonight, you could probably add another 4 tomorrow or Sunday. I'd wait till Sunday--patience is probably the hardest lesson in this hobby. ;)

[yashinfan]

So everything will be fine by sunday? Excellent :) My dad told me to wait a week, but I thought that would be over-cautious. My next question is: Does it matter in what order I add the fish? For example, if I bought 4 females and added them, would that make any difference than buying 3 females and one male? It may be a coincedence but I found that the pairs I have bought each time seem to be more attached to one another. Do you think it is best for me to choose the biggest females and males if I am trying to breed them? Or is there a chance that these fish will be past their prime? lol, I sound very obsessive now. Sorry to ask so many questions but I really want everything to work out :)