Pond Boss Forums STOCKING A NEW POND Raising Forage and Bait Minnows for a Canadian pond?

Your sunfish or RES as you call them are very likely pumpkinseed sunfish (PS) which also have a red tab on the gill flap. PS are more colorful than RES. True redear sunfish will not survive the winters in your far northern zone. PS are common in Canada.

I think the best approach for your fishery is:
1. Emphasize the trout and feed them to make them grow better or faster. Any other fish that learn to eat the trout food will benefit by increased growth rates. Do not over feed which could tend to make your pond more cloudy due to more plankton growth. But since you probably have some constant flow-through or over flow, cloudiness from plankton growth will tend to be reduced or a minimal problem.
2. The mainly, pretty cool temperatures of your spring fed pond will tend slow down the growth of the other non-trout fish present. Your other non-trout like warmer water for good growth rates.
3. IMO increasing the abundance of small fish in your pond will best be done by not adding more forage fish but by reducing the numbers of bass that are primarily responsible for eating close to 65%-85% of your small fish. If you feed the trout pellets then this percentage will then be closer to 86%-95% small fish consumption by the bass. Trout "on pellets" eat fewer forage fish. Thus if you focus the fish harvest on keeping bass and add some fish structure or cover (tree brush) as suggested by Adirondack, then you will see an increase in numbers of small perch and PS. True suckers will not spawn in your pond. If you see small sucker-like fish, IMO they will not be suckers but some other species of fish. If you don't see small fish numbers increase by the next year or two, then you have not removed enough bass per yr. Remove bass till you see number of small fish start to increase.
4. If small fish seem to become too abundant then reduce the number of bass harvested each year. Bass will continually reproduce each year to provide a constant supply of too many predators present. Bass tend to do that.
5. I doubt that the suckers eat eggs of the bass or sunfish. Nest builders (sunfish, bass) defend nest and eggs from intruders including suckers. I'm not sure the suckers will even eat the unguarded perch eggs. Perch eggs are supposed to have an off-flavor that helps deter other things such as fish and birds from eating them. If you suspect something is eating the perch eggs try putting some of the laid YP eggs in a floating laundry basket or other container that allows water flow through yet excludes swimming predators. Eggs will hatch (7-14days depends on water temp) in the container and fry will swim out into the open pond. If your pond water is quite clear, it has few zooplankton, and perch fry have little to eat when they hatch thus survival could be low partly due to this.

6. If you have "lots?" of small (1"-2") sunfish and few 3"-5" sunfish then the bass are primarily eating and cropping the larger sized sunfish and mostly ignoring the 1"-1.7" size. Again reduce the bass numbers esp larger bass (12"-14") and numbers of larger sunfish and possibly perch will increase. Larger perch (6"-10") will also readily eat small 1"-2" fish.

7. If your emphasis is catching larger fish of 16"-22" then emphasize the trout by feeding pellets.