CPO lost her eggs

I have a couple of females and they were recently berried. They had then carried the eggs for about 2 weeks (and the eggs changed from greyish black to orangy in colour during this period). Couple of days ago, I realised that the CPO might have lost her eggs as the eggs were now greyish black again.

Any idea what happened?

[lucas_1957]

Can state your parameters and tank specs? Eg tank size, number of CPOs, hiding places, temp, pH

[bettafantastic]

My CPO eggs also black one...but still hatch in the end..

tank is in the office so don't really monitor the water parameters. It's definitely neutral to above pH 7. 6 CPOs in a 1 feet tank, with driftwood, caves and plants to serve as hiding spot.

temp is a little warmer (shouldn't be more than 30) as I keep the lid closed. clamp on light is switched on 8 - 10 hrs a day. other inhabitants include galaxy danios, oto, panda cory and zebra snail - all of which are friendly neighbours.