Unfortuately what you are experiencinng is the norm for WA freshwater fishing, basically all of the dams are over run with runt Redfin. If you persist or get lucky you eventually hit a school of bigger ones. The Warren River generally has a larger average size than the irrigation dams, have see some good ones come out of the Capel and Preston Rivers too.

 You are in the right areas.  Maybe well upstream on the murray/hotham or below scarp pool on the murray but it is very hard work in rugged country.  Bigger fish in the warren and some good fish in big brook dam.  Have got some good ones in recent years but outnumberted 20:1 by runts.

Try using a runt size reddie as bait make sure the hook goes through the back in front of the dorsal fine and is a sharp hook. You would be surprised how you can "up size" the bait in regards to the redfin being caught. You are fishing the correct places just make sure the soluna chart shows a major activity of 8. Another tip is if you have a pet dog and it starts going ape in the garden - go fishing as this is an indicator of a major fish fedding/activity time. keep trying then post some pics.

Hope this helps

 Thanks for the tips guys, all helpful info. I have considered sending a runt out as a livey Redfinman but thought better of it. I'll def give it a go now though. Some nice fish you have in your avatar pic mate.

Fish the Warren River. It's full of good sized Reddies. Fish beside snags with two inch plastics, in a tea bag up and down type motion. It's a it further than Harvey, but it will give you what you are chasing.

 Waroona goes alright, bear in mind these things have a big gob and an appetite to match. These were jigged up out of 20ish meters with 60gm demersal jigs. 4-6" livies are the best method of getting really big Reddies but it's not as much fun as jigging. Big Barra sized placcies work too.

http://fishwrecked.com/files/smicko/20130426_174532_0.jpg

 nice reddies there.  Good fillets there.  One of the better eating fish on the plate.

 troll big minnow lures in black and green stripe pattern an hour before dark up the back of drakes brook weir along the weed beds.200mm or bigger you should not get a perch smaller than the lure.been doing it for thirty years biggest was 3 lb plus at 200mm they are worth filleting and skining.casting big wonder wobblers towards the banks works good as well

 In drakes use deep diving lures also but watch the fence lines- I have lost a few good lures on the underwater fences .  Electric only or paddle on Drakes