How do i get my longfin bristlenose (ancistrus) to spawn?

i have a pair of longfins in a 20 gallon long. i have had them for 4 weeks and the guy i got them from said they should spawn soon. i feed them alge waffers, do 25% water change weekly, theres wood and three caves. what do i do.

Turn the lights down low, Turn on some Al Green music, and dump some wine in the tank...lol Just give them time. It takes time for fish to get accustomed to the surroundings.

It took my Albinos 3 months. On some of the other pairs I just switched around the males and they had eggs in a week.

And it depends on how old they are . I got some juvies and it was 10 months before they became sexually mature . Just give them time and nature will take its course !

i had similar issues until i made the opening to the cave smaller so that the parent fish have to almost squeeze through to get in ,i have babies coming out my ears,

2 batches in a very short amount of time,

one cave ,small entrance worked for me and another fella who breeds them told me to do it.

im jeff ,im new here ,,,,hi

the light is almost never on and the male is 2in long, body not fins, the female is 3in long. they have spawned before but not with me. ill try make some smaller caves and see if that helps.

how old do they need to be to spawn??

They need to be bigger then 2". I would also say that the male needs to be bigger then the female. He is tyring to trap her in the cave and basically force her to mate with him. If he can't trap her in there then in her eyes he is not good enough to mate with her.

Are you sure you got a M and F?

greydragon12345 wrote:

how old do they need to be to spawn??

Anytime after 8-9 months they will become sexually mature.

they have spawned before.

For you or the person you got them from?

person i got them from

fifty5gal wrote:

person i got them from

Do you trust that person 100%?

I just don't see them spawing that young with the male being smaller then the female. Just my opinion but I have seen weird things happen

yes.

If you do, then I guess all you can do is wait. Patience is key in this hobby.

at the size you say they are ,, I have my doubts ! They prolly need to be another 3/4 in. body size . The females body will get really wide as she gets eggs ready ! And you can actually see the eggs if she is on the front glass .