For an anti-dog lid ... and maybe to deter fruit flies if they become an issue ... I was thinking of getting some EZ-Strainers ...
http://www.usplastic.com/catalog/item.aspx?itemid=24071
This is a product designed to fit into the top of a 5 gallon bucket so you can screen debris out of "liquids" like paint.
I don't think it would work to "strain" FF because in my experience the extra liquid in FF wants to be on the top of the feed, so gravity straining FF doesn't actually work in any case, but certainly not with screens this fine.
BUT ... it would make a great "lid" for a 5 gallon bucket of FF because it would let the bucket breathe. No explosions! Always a bonus.
............
Just to recap and give an example of a slightly different system for managing FF that works for my situation:
I have a 5 bucket system ... 5 gallon buckets. I feed a complete 5 gallon bucket of feed each day (feeding over 100 birds, and they also have access to dry food, and YES I do wish things could be arranged so I could reliably provide them with exactly the right amount of FF each and every day so I can take away the dry feed, but I'm not "there" yet and don't know that I ever will be).
IF I'm adding supplements to the basic feed, I stir them into the bucket right before serving the FF.
When the bucket comes back to the kitchen it is empty. I take a couple scoops of feed from the "oldest" bucket and add it to the newly-empty bucket. Then I add in the 2.25 gallons of fresh well water and give it a good stir. Then I add in the the two gallons of feed and stir until it starts to break down and absorb the water. When it starts getting thick enough that it's tough to stir, I let it sit and ferment and "only" stir it twice per day ... morning and night.
To stir I use three different things depending ...
I have a big industrial spoon I use to stir the water into the scoops of feed to "backslop." I also use this spoon to shift the feed from the bucket into the feeder. I love this spoon.
I have a HUGE industrial whisk I use to stir buckets that are up on my counter ... more of a poke, poke, poke than an actual stir cuz the FF is super thick.
I have a manual cement mixing tool I use to stir a bucket if it's on the floor. If I brace the bucket, I can "twirl" the cement mixer, and poke, poke, poke with it and it really does a great job of stirring clear to the bottom and edges of the bucket. Because I can't use my arms much, I often have Dad help with the stirring.
I asked Dad if he would prefer to have a big cooler with a big batch of FF in that, so there is just one thing to stir, and he says he prefers the individual buckets.
We reserve the right to change our minds about any/all of this, though.
AND ... for what it is worth
... I've been working with a animal nutritionist (she is super passionate about this! she is so informed! so plugged into the local sources! and a bit of a marketing wiz on top of all of that) at a local feed company to come up with a flexible custom feed that will meet all our needs here, and to which we can add "supplements" when we have temporary/unique needs. We discussed fermenting, and she says she is a big fan of it! So ...
(She told me she has some customers who call her every time they have a question, and often it is the same question they called about last time. She says she sometimes has to tell them, "You're going to have to write some of this down because I can't keep answering these same basic questions." And she says people do get their feelings hurt by that, but ... ).