Well my new lot of eggs are doing ok, not a huge amount but that's no big problem.
One egg in the middle of the bunch went bad so after last time losing 95% the day after one went bad that I couldn't access I decided what the heck I can't do any worse than last time letting them all go bad. Let's see if I can seperate them, I was initially thinking I would use a small sharp pair of scissors but couldn't single out the eggs to seperate them. Same issue with trying to use a scalpel. My solution was 2 straws. Yes who would have thought, placing the eggs in a shallow bowl with some of the tank water you can gently place the straw over a egg on one side of the bunch the. Select eggs opposite and one at a time slide the straw over the egg and while pressing the straw onto the bottom of the bowl twist it a bit and it will cut the attaching string, if not it almost cuts the string and a gentle slide of the straw away from the bunch and it comes free. Out of 20 eggs I damaged a total of 3 with this method. Today the embryo vein is showing in all the eggs so I class that method as quite successful at seperating the eggs.
I will try video it next time to give a better idea of what I did.