Male Betta & His Bubble Nest Problems

Hello.
 
I HAD a male and female betta in the same tank (2ft tank) together, then was warned to keep them separate. I went to inspect the tank, do a water change and to figure out a plan. They were right in the middle of spawning!!!
 
She was dropping so many eggs, he was scooping them up and putting them in his "nest", she was also helping him do this.
 
But I noticed, he didn't have much of a bubble nest formed.
 
He did everything right, but his nest was terrible! It was small, didn't hold the eggs very well, and not long after, the nest was completely gone!
 
Because I wasn't planning to breed them, I didn't have the water levels right, so I know that would have tired him out (poor thing) and most likely gave up on it...
 
BUT my question is, why wasn't his nest very good prior to her spawning. Ive read that they usually start to nest once the female is in sight and she is showing she is ready to release her eggs, but he didn't seem to get very far...
 
You can see in some photos, the eggs look as though they are just floating there, that was about half way through and the bubbles were pretty much gone!
 
I would like to know about the nest more as I would like to breed them the correct way! My poor darlings.
Any help would be appreciated.

and also, I know this answer may vary from breeder to breeder, how long after they have spawned, can I try again?

well my guess is that it was his first time making a nest, and he didn't know what he was doing. next him allow him to build a large nest and keep the female separate but visible. (get a separator or something)
this'll provoke him to create a bigger nest because he now has to wait for the female and when you think the nest is good enough then take the separator out.

Some males never make "good" nests but they can keep a spawn afloat so it all depends on the individual betta.  Now in saying that, my thoughts are that neither of them were conditioned to breed which helps with nest making as well.  I suggest not breeding until you research it fully and make sure you can accommodate all the needs of the breeding pair and the young fry which includes having separate containers to hold over 100 bettas and having tiny live foods.  

Ok thanks.they have been separated ever since.the tank has a filler that's set on low, and is more like a soft waterfall, heater is set at 28. They have plans but not real. Getting real ones today. They are feed twice a day, bloodworms. they are in a room on their own (our house is small and didn't want them near a loud TV)
If they attempted a spawn before, would that mean I'm on the right track?
Also, if the female gets a belly full of eggs, but I don't put her in with the male, will she still release them on her own? I don't want her getting sick!

The female will be fine to stay by herself.  She shouldn't get too full of eggs and it is rare to have a female become eggbound.  Most females will either absorb the eggs back into the body or release them.  Just because they spawned/attempted a spawn doesn't mean much more beyond the fact that you had a male and a female that are of a mature enough age to spawn.  
I recommend you feed something other than bloodworms all the time.  They are great for a once or twice a week treat but the daily diet should be a good betta pellet.

was there something in the tank making the water move around like a filter or bubbler?