After spending several months working out how to do this I feel I can at last say how it can be done.
The essential requirements are:
1) Soft Water at approx 80F so the danios will breed in the first place
2) A heavily planted community tank
3) No fish such as plecs or angelfish which avidly eat fry/eggs, but cardinal tetras, swordtails rasboras and barbs are ok.
4) An external canister filter. Mine is ehiem ecco and I have the large inlet unit. The inlet unit pipe comes down and then does a 90 degree turn at the bottom so that the inlet is in a horizontal position. Keep the inlet cage on so that the adults don't get sucked in. I can't guarantee this will work with all canister filter types as I havent tried with other filter types.
5) A large amount of micro vallis/hair grass placed around the filter inlet.
The fish, provided they are well fed, with at least occasional live or frozen food such as daphnia or cyclops, will spawn often. You may or may not see them do this in the mornings. They will scatter eggs all over the tank and some spawning will take place in the plants beside the filter inlet, with the eggs going straight up the filter. A tank which gets some early morning sun seems to help spawning.
Every 2-3 days or after seeing the fish spawn, disconnect the filter from mains and tank and empty the water from the filter canister into a small tank or bowl. Once the dirt settles look with a careful eye and in a well lit place and you will see eggs and newborn fry. Up to 30 per spawning can be achieved. 10-15 is more typical with 2-3 for smaller species such as D Nigrofasciatus which lay less eggs
Use a pipette to stir up the dirt to reveal and extract the eggs and fry into a fry tank filled with water from the main tank - don't leave them with all the dirt from the filter. Once the fry are free swimming feed on infusoria or powder fry food until the fry are large enough to go into the main tank.
For a few days after the inital collection of eggs/fry, disconnect filter from mains and tank and empty the canister every day (as detailed above) because some additional fry who hatch in the community tank will get sucked into the filter. Probably only one or two a day but they all count.
I have also had live baby swordtails in the filter and, although other egg layers such as barbs or rasboras lay sticky eggs which wont go in the filter, a few fry might get into the filter. Less likely with characins but you never know.
So far I have raised approx 50 fry successfully this way including D Kerri, D Abolineatus, D Rosues and D Nigrofasicatus and a couple of fish that are possibly hybrids (inevitable with community tank breeding) One of the best things about breeding this way is getting fry and only finding out what they are when they grow.
The essential requirements are:
1) Soft Water at approx 80F so the danios will breed in the first place
2) A heavily planted community tank
3) No fish such as plecs or angelfish which avidly eat fry/eggs, but cardinal tetras, swordtails rasboras and barbs are ok.
4) An external canister filter. Mine is ehiem ecco and I have the large inlet unit. The inlet unit pipe comes down and then does a 90 degree turn at the bottom so that the inlet is in a horizontal position. Keep the inlet cage on so that the adults don't get sucked in. I can't guarantee this will work with all canister filter types as I havent tried with other filter types.
5) A large amount of micro vallis/hair grass placed around the filter inlet.
The fish, provided they are well fed, with at least occasional live or frozen food such as daphnia or cyclops, will spawn often. You may or may not see them do this in the mornings. They will scatter eggs all over the tank and some spawning will take place in the plants beside the filter inlet, with the eggs going straight up the filter. A tank which gets some early morning sun seems to help spawning.
Every 2-3 days or after seeing the fish spawn, disconnect the filter from mains and tank and empty the water from the filter canister into a small tank or bowl. Once the dirt settles look with a careful eye and in a well lit place and you will see eggs and newborn fry. Up to 30 per spawning can be achieved. 10-15 is more typical with 2-3 for smaller species such as D Nigrofasciatus which lay less eggs
Use a pipette to stir up the dirt to reveal and extract the eggs and fry into a fry tank filled with water from the main tank - don't leave them with all the dirt from the filter. Once the fry are free swimming feed on infusoria or powder fry food until the fry are large enough to go into the main tank.
For a few days after the inital collection of eggs/fry, disconnect filter from mains and tank and empty the canister every day (as detailed above) because some additional fry who hatch in the community tank will get sucked into the filter. Probably only one or two a day but they all count.
I have also had live baby swordtails in the filter and, although other egg layers such as barbs or rasboras lay sticky eggs which wont go in the filter, a few fry might get into the filter. Less likely with characins but you never know.
So far I have raised approx 50 fry successfully this way including D Kerri, D Abolineatus, D Rosues and D Nigrofasicatus and a couple of fish that are possibly hybrids (inevitable with community tank breeding) One of the best things about breeding this way is getting fry and only finding out what they are when they grow.
