Oscar wigglers are 1/16th" - 1/8"or so , it depends on the size of the eggs really, oscar eggs will just look to suddenly have tails then eyes.
Be ready for more fry then Blue Gouramis have.
Here's a full size batch of eggs (the other was mid-laying)
[img]http://cjexotics.com/images/albeggs2.jpg[/img]
Once they become free swimming fry they'll be 1/4" pretty fast.
Growth to an inch varies alot , dependant on food (type and quality) , temperature , water quality , if they're raised by the parents , if they raised alone , etc...
The stuff I like best for feeding baby oscars (most of my cichlid fry) is cyclopeeze
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The freeze dryed is ok, personally I liked the frozen better though.
The stuff runs about $50 shipped to your door for around 2 pounds of it.
Sounds expensive but in the end it's a lot cheaper ,less time consuming,less hastle and gives better results then trying to hatch brine shrimp.
I get mine [url=http://www.jehmco.com/html/cyclop-eeze.html]here[/url]
I "think" they may have 4 ounce packages for less,not sure though I usually grab a few bricks at a time.
otherwise - baby brine shrimp work
- crumble flake foods work too
but both tend to foul a tank faster and take more maintaince then cyclo-eeze.
[quote]i will do some more reasearch on those convict cichlids and see if id like to try and breed those instead.[/quote]
Short quick run down on them.
They will breed in a mud puddle .
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They're reccomended often because they're smaller , spawn younger , spawn faster and are cheaper (purchase and care) then Oscars.
They're also easy to visually sex , since (99% of the time) females have orange sides , males don't.