hello i have about 20 to 25 fry in my crib thing and i was wondering how long i should keep them into there b4 releasing them into the tank with all my other fish/give them away to my friends. i currently have a bunch of random fish including 6 goldfish an angel fish and some other mollies in a 20g tank

Are we talking about molly fry? How old are they? I guess they need to be large enough to fend for themselves when they're out. I'm sure others with specific experience will chime in. I'd say not less than 1-2 months but it's a function of how fast they're growing. You can also take a couple out when you think it's time and see how they manage. BTW, I'm concerned that you might have too much fish in your tank. Please keep an eye on water chemistry and do large weekly changes.

You are way overstocked, so unless you are doing massive water changes, the growth of the young fish will be slowed down.
Angels are ambush predators, so your young need to be at least 3/4 of an inch to have a chance, depending on the age of the angel.
But with six goldfish, you are going to be in trouble fast. Goldfish need 20-30 gallons each, longterm. They are also not compatible with an angel, which is a tropical species. Goldies should be in colder water. Mollies and angels like warmth, but mollies need hard water and angels like soft water...

ya i kno guys my professor was giving away goldfish and like forced me and my buddy to take a bunch because she couldnt get rid of them. im doin like a 25% water change every 2 wks and are tryin to find a new home for the goldfish that i didnt want in the first place

and the guy at petco said about for every in of fish u should have a gallon of water and im pretty sure i do abide by that rule

The one inch rule really breaks down on goldfish - one inch long, two inches up, one inch wide... there are a lot of inches in an inch of goldfish.

Not to mention that for one inch of goldfish, there's two inches of poop daily.

You still need to get the mollies up to too big for the angel. When I said 3/4 inch, I was thinking adult angel. If the angel's smaller, you might get away with 1/2 inch.

ok thanks for the heads up. and im definetly going to wait until the 3/4 in just to be absolutly sure that they will make it. thanks for the help

Just to chime in, you should probably do that 25% at least once a week.

Now about the fry, the general rule is that if they are big enough to not fit in the other fish's mouth they should be OK, however as already mentioned Angels may cause some problems. I had 8 Molly fry in a breeder net for about 8 weeks before I released them into the main tank and even though they were already quite big some of the adult fish still went for them, of those 8, 2 did not make it but I think that was due to stress rather than predation. The remaining 6 are doing brilliantly now and are never bothered by the other fishes.

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45g pentagonal
4 Swordtails, 2 dwarf Gouramis, 5 Mollies, 1 Rainbow Shark, 6 Molly fry 6 zebra danios

88 gal Malawi tank
4 Yellow labs, 1 Baenshi, 2 Borleyis, 3 Trewavas, 2 Livingstonis, 1 Venustus, 2 Green Terrors

thanks again guys i am trying to get rid of the goldfish i cant find anyone to take them though i will start doing those water changes once a week. thanks for all the help

If they're in good (sellable) shape, your local fish store might take them. Good luck with that.

Do you know anyone with a pond? My roommate in college had a cool indoor pond, that she moved out onto the deck in the summers. It was a small animal trough with a large filter on the back and some pond plants. She kept gold fish in there, and it was a lovely water feature in our house/on the deck.

If you're stuck with them, that's a relatively cheap/fun aquaculture project.

Chessie