I have a pair of kribs in my 30g long and they breed like crazy. I got my first batch of eggs a few weeks ago and they just laid eggs under my slate again yesterday. I must say, they get EXTREMELY aggressive when breeding. I'm not talking a little nipping if they come your way - I'm talking the other fish are practically trying to jump out of the tank! Even my large (6"+) koi angel doesn't want anything to do with them. The male harassed my last neon (probably 2 years old) and 4 von rios to death before I separated them.
My female is an excellent parent, scooping up wandering fry in her mouth and spitting them back into the cloud of fry. The male started off good, tending to the fry, guarding their slate cave, etc. Then all of a sudden he decided he liked to eat the fry and the female didn't take it so well. They started fighting, the male won I'd say. The female had her tail fin pretty chewed up but two weeks in QT fixed it right up.
This time I put them into the main tank and let them lay their eggs. Once the fry hit free swimming I am going to suck them out of the tank with airline tubing and put them into a grow out tank. I have a LFS that is willing to buy them off me so I do want survivors.
First batch of fry was somewhere in the 60-80 egg range. Probably half survived to free swimming. The second time (yesterdays batch) is probably a little larger, maybe closer to 100 eggs.
As far as parameters... ammonia 0, nitrites 0, nitrates 15ppm (I dose nitrates for my plants), pH was around 7.4 the last time I checked, CO2 30ppm. Tank is moderately planted right now, just rescaped and got new plants so it is still growing in. Playsand substrate with lots of red slate for hiding places. I'd say sand is a must as the kribs will dig a pit to breed in (mine happened to like under a piece of slate). If you have any other questions feel free to ask! Hope it helps!
