Angel breeding...never successful

Hi all,

I'm posting this on behalf of my pair of angels, who have spawned
probably around 9 times now, never yielding a batch of fry that live
past the wriggler stage.

1st time: parents eat fry. That's to be expected.
2nd time: leave parents in, fry get to be wriggling, with some
experiencing bursts of free-swimming in the water. The next day, all
fry are gone
3rd time: figure I ought to take the parents out this time. Wait
until they're starting to freely swim, then remove parents. By the
next morning, white corpses dot the graveless bottom.
4th time: do same thing, but add meth blue. Babies still die.
5th time: maybe babies dying b/c they're settling on the bottom too
early. Need parents to keep them off bottom, so I leave parents in
again. They still eat babies.
6th time: removed parents, and also java moss, which accumulated
debris that could've lead to increaced bacteria content in tank.
Babies still die
etc.

So a couple days ago, the babies started wriggling, I moved the
parents out, and dropped about 20 drops of meth blue in the 30 gallon.
By this morning, there were only two babies that were still alive,
but just barely.

What else can I try? Increase the concentration of the meth blue? (I
tried about 1 drop per gallon previously--still no luck) Add the meth
blue at the egg stage, even though few (about 2 or 3) of the eggs
actually succumb to fungus? Start feeding them (they're not free
swimming, so I figured they wouldn't be able to eat yet)?

Any advice would be good. At least to make them live past the first
week.

A few years ago, I was able to raise a single baby to about a month
old, but alas, that one died as well.

(emails won't work--pls post )
tim