Just FYI, a 4" Siphon will drain about 1200 GPM and a 6", about 3000 GPM.
In a pond only 6 acres, I'd stock Threadfin Shad over gizzard. but gizzards do reproduce faster. Problem is when they die off and pollute the water.
7,000.000 gallons in 6 acres would be an average depth of only ~3.5'. That's pretty shallow. Most run around a 6' average depth, which would be ~11,700,000 gallons in roughly 36 acre/feet of water
