I feed mine twice a day with newly hatched brine shrimp.

I think you can't quantify heavy feeding by how often you are feeding, but rather how much (total) you are feeding.

If you are feeding more than your fish can eat in a 5 minute span at any one time, then you're probably feeding too much. However, that might not be enough if it's only once every two days, or even once a day. I think it would be better to split the amount your fish can eat in 5 minutes into two, and feed twice daily.

Easier said than done sometimes when it comes to frozen foods. I feed pellets every day in the morning (only as much as is eaten in a 5 minute span), and add to that a cube of frozen every second day (most of it gets eaten). I would say that this is 'moderate' feeding; I've been thinking of adding pellets to the afternoons I don't feed frozen, but on the other hand, there really is no need at this point. What I'll probably do instead is add an algae grazer ring or some nori on a clip on those days, once I get my Kole tang and foxface in there.

I feed, each feeding, enough to saturate the water column. No way the fish can get it all, so that leaves scraps for the shrimps and crabs and other critters.

I use to overfeed but that lead to a algae outbreak that I didn't fix right away n turn my tank into crap n smothered many zoas n sps to death. Tried to add some Gfo to soak up the extra baddies in the water but added too much and destroye my tank. It's now in the process of recovering. Tricky hobby

I feed some sort of algae in the morning and then feed my fish a mix of frozen foods in the evening until they stop eating (and they actually do) and their bellies are fat!!! That can be 5 mins or 10. My system does not like pellets so I stay away and only use as a last resort (out of frozen) but won't add on an auto feeder.

Based on this thread, I think I'm underfeeding and should be adding more. Just not really able to do so.

Whats proper filtration? What's heavy feeding? What type of environment are you trying to maintain?
We can feed a 100% of whatever we have the means to remove. If we could remove 100% of what goes in we could feed pails of food as many time as day as we'd want to. If efficiency is not 100% then what's added needs to reflect that. If feedings are heavy in the sense they are greater then the rate of removal, then yes there can be very real possible issues with doing so depending on the type of envioroment you wish to maintain. If you don't want but have nuisance algae and/or you need to clean your glass daily or every second day, chances are additions are far more then you and your system can effectively remove/process in a timely fashion. But if fish are starving and we can't add what they need because the system cannot handle it then we really need to re examine our current husbandry practices.

Feed as much and as often as you wish based upon what you and your system can remove and process effectively in a timely fashion. You may find your once thought of idea of heavy feeding is easily maintained by you and your system, or you may find keeping happy fish could turn out to be unhappy you with and algae farm.

yup that be my way too

Wow Im really under feeding, also don't you people work? lol

I feed one large pinch of dried brine shrimp once a day, one large mats of purple veggie twice a week, and a lot of frozen brine, mysis, cyclo, reef roids, phyto and bloodworms once every 3 days or so, that are rinsed thoroughly and plentiful, and silverside by hand to the lobster, all with the pumps off. I maintain low nitrate and undetectable phosphates, and over-skim. I'd say I grossly underfeed. ;) But the fish are fat, happy, and visibly healthy.

Though now after reading everyone's comments, I'm considering feeding more, daily.

If your or my fish are fat, healthy and happy why do we need further additions beyond that point?