Like Bryan mentioned, it can crash quick

Had it happen when we were raising clown babies.
We used 5 gallon buckets -- as I always do, we went overboard and was raising tisbe, tangerine, rotifers, and a couple of others -- had a total of 7 buckets going lol 2 for phyto (nano and ..? one more that was brown), and 5 different strains of pods. Initially everything was happy and dandy, but after a week or two, I started getting lazy and that's when problems started happening.
What worked:
-- We kept them at room temperature (no heaters)
-- We had 1 airstone in every bucket, with air output controlled via gang-valve
-- We were feeding them phyto from the phyto culture every day to every other day
-- Storing some pods from every culture (basically every day) in the fridge in-case of a crash in the grow-out system
What didn't work:
-- Need to clean the buckets every day or 2 days max (they started dying creating an ammonia spike crashing the entire culture)
-- Cat and Dog fur in the bucket
-- Need to clean the buckets every day or 2 days max (they started dying creating an ammonia spike crashing the entire culture) (mentioning this again on purpose)
-- Annoyed wife from having half the fridge full of bottles with phyto and pods
-- Having to completely wash my hands, top to bottom, after working on each bucket, so I don't cross-contaminate the cultures ... especially when going from pods to phyto ...
But really, as long as you can keep up with the cleaning and harvesting, I think you'll have fun. I didn't use a sieve to harvest them -- I tried it but didn't like it -- water took forever to go through those tiny holes and I'm a very impatient man; I just ended up taking water out of the buckets because all the pods were floating around anyway, and replacing the water. Maybe this was the reason my cultures crashed one after the other? who knows ...
My advice:
-- Keep it simple; grow tisbe or rotifers (they were the hardiest and easiest to grow)
-- If possible, use a cone shaped item (maybe upside down soda bottle) so that to get rid of the "dead" stuff, you can just open a valve and be done. OR have a couple of containers and keep rotating them. Having to clean the bottom of the bucket and walls with a sponge everyday was a PITA
I think that's about it ... if anything else comes to mind I'll post.
Hope that helps!
- Archit