Got his water parameters:
pH = 6.0
GH = KH = 1d (well, the color changed after 1 drop so I guess it is between 0 and 1).
He changes water on the breeding tank daily and also feeds live blood worms, frozen beef heart, etc.
To me, he seems to be doing things right...
Oh and today, they spawned again... This time, some of the eggs show some black elements but again, # of eggs have gone down fast from over 100 to now like 40.
Hmmm...
There are a few things I would like to say,
1: Our optimal TDS settings are 120ppm for maximum fertilization and hatch rate.
When the Osmotic pressure drops below the optimal point the eggs become over fertilized and erupt, when the pressure is to high the eggs get hard and do not allow sperm to penetrate properly.
I am not an expert , this is just what we have discovered in our own hatchery, We currently have 9 Pairs of Discus with eggs and free swimming fry , so we must be doing something right not to mention around 300 Juvies we have left after selling over 2500 last week.
I still think it is the Male that is not doing his job!!!
We have Pairs in Hard water that are getting some free swimmers ( water around 400 ppm TDS)(PH 7.6-7.8) They are not doing near as well as the pairs in softer water , with a PH of 6.5
Just my opinion.