You need to feed the rots phyto. Rots that haven't eaten anything in 2 days have virtually no nutritional value (at least not enough for clown fry) "“ just because they can live for 7+ days doesn't solve the problem. Also, even though it looks like a lot of rots in the bag, I'd speculate that amount is only probably enough for 1-2 days (depends on the hatch size though). Clown larvae consume large amounts of rots due to the fact that well fed rots still aren't that nutritious "“ size and ease of culture is why they are fed (not quality).
The least maintenance route you could go is to buy the bag of rots, drop them in a 5 gallon bucket with an air stone, buy some non-live phyto to feed them every day (keeps you out of the algae culturing business) and feed them Oto A (or very finely crushed flakes/pellets) starting with day 6-8 (baby brine is an alternate for Oto, but you'd need to hatch). I personally go rots to day 6, BBS to day 20 and Oto the rest of the way out. I culture my phyto too because it is cheaper than buying, but it does require more work.
To be honest, if you don't have all of this already "“ I'd let the hatch pass until you are prepared. It is really hard to play catch up on hatch "“ not impossible though.
-John