Hi whale88
I know what you mean.
I thought that at first so I used to turn my pumps off for an hour or so on a timer,but now I think the faster the flow the more they fight it and the food moves around a lot more.
You must remember that any fish needs flow in the tank to condition and develop their muscles if you don't have enough flow they will not and will be under developed and zebs are evolved to tolerate fast flowing water,also they use more energy fighting the currant and use more of their reserves and thus healthier fish and having to eat more.
IMO. The food will collect in other places in any tank with bare bottom,gravel,sand,wood,rocks ect,but on the whole if the food is moving around the tank as in passing the fish I find they are more likely to eat it as in the wild.
Where it collects they will eat it but I have found not so well I think its due to say two fish same place for food they end up doing more fighting and chasing than eating I don't hardly ever see two of my zebs in the same place eating the same food for long but if food coming past they don't need to move far from their spot thus less confrontation from other fish and more feeding time.
Its not a necessity to have the food moving around the tank I think you get better results from it.
In my fry tanks the food is crushed for them and I try to get the food particles to stay suspended in the flow for as long as possible hopefully till its eaten or collected on the filter sponged uptakes and they love it.
The food does collect in places in those tanks and if I leave it over night there usually is some in the morning so I actually after a while rake it off the bottom of the tank and the filter uptake sponges and round it goes again.Feeding in a faster flow also the food is distributed more evenly between the fish.
Obviously this does not apply to the heavier food like whole tablets,peas ect.
Hope this helps.
Jerry