for my 65-gallon, I feed my tang a .5"X2" piece of dried seaweed daily because violet looks better when she's fat
for the rest of the inhabitants : two percula clowns, 4 chromis (like damsels) and midas blenny (picture by my posts) they get about 8 BB-sized soft pellets a day - probaby equivalent to a good pinch of flakes - and I think I'm still overfeeding :lol:
The hermit crab and skimmer are competing for two different kinds of food - the hermit will be fine getting the scraps of food dropped by the puffer fish (they're messy eaters) so the two of them make a good pair - this doesn't mean that you should feed your puffer extra food - just enough food for it to eat in a minute or two while you watch - if it gets dis-interested, feed less the next time.
Keep in mind - crabs are opportunistic - they'll eat food scraps, algae, small 'pods, and if they're hungry enough - or looking for a new home - they'll eat snails too - I'd use that as a good indicator of if you're feeding it enough - if you see a lot of empty snail shells, you might want to toss the guy a bone to chew on.
Personally - I don't have any hermits in my tank, as I like my snails a little more than them (they just eat that algae I don't like) - but that is a matter of preference. As long as the hermit is pretty small they shouldn't harm any fish and just harmlessly graze on nusiance algae - but some of those big bruisers that are the size of a golfball or larger definately have the capability of grabbing a damsel or other similar small fish while they're sleeping - just so you know.
If anything, the micro-fauna (small copepods, bristleworms, and the very, very small stuff you can't see except for with a microscope) are the animals that would be eating what the skimmer is pulling out - but this shouldn't worry you, as you don't have live rock, so you won't have an abundance of these critters - crank that skimmer up and pull out as much gunk as you can :thumbsup:
Brine shrimp have a pretty bad reputation for not having any nutritional value; If you have "enriched" brine shrimp, those aren't too bad, probably about as good as anything else - flakes are also appropriate for the type of livestock you have.
Puffy would probably enjoy some fresh shrimp (a 1/4 lb of the fresh tiger shrimp at the grocery store won't have preservatives (phosphates) and will probably be cheaper than LFS-bought food) and all other types of freshly-bought seafood from the store - it can be fun to experiment in the kitchen with some new seafood recipies for you and your family, and save a small stockpile of fresh seafood in the freezer for puffy. shrimp still in the shell will help their teeth - as would a crayfish (not everyone is too cool with that though
) feeding a whole shrimp will probably be way too much - small 1/4"-1/2" pieces would be best.
As far as feeding frequency and amount goes - you can probably not feed your tank for a month without your fish looking "skinny" at all; It has been done with reef tanks - but they can cultivate a lot of supplemental live food - so I wouldn't try it with yours quite yet. As hobbiests, we tend to really over-feed our fish, and this can lead to a lot of problems over time - which won't make sense to you as you don't feel like you're over-feeding, but water quality will suffer and algae will begin to over-grow your tank in epic proportions for no apparent reason.
If you want to feed your tank three times a day - that's good, but make the feedings as small as possible - keeping a good eye on how much the fish actually eat, and how your nitrates climb over time. Keeping a log book during the first few months should let you know how fast your nitrates are rising - and what kind of water change schedule you will have to use to keep them at acceptable levels.
For example, if you can feed your fish 1/2 as much, and they're still healthy, and your nitrates only climb 1/2 as fast - you can reduce your water change schedule from once a week to once every two weeks. If you can reduce feedings by 1/4 - 1/4 the water changes (or so) - you get the idea.
I guess my point is that it is extremely easy to over-feed your tank, I personlally think that it is probably the reason that a lot of people fail at keeping saltwater tanks - they think they require more care - which they translate to mean more feedings.... leading to poor water quality and dead fish - so when it comes to feeding, err on the side of Less is more
did I mention that I love Fridays at work