I have a dedicated FHM pond. It is about a 50 x 40 foot oval and 4 feet deep, but average depth probably 20 inches. I had it built in November 2015 and stocked a few pounds of FHM in March 2016. It is now wall to wall FHM. I trapped probably 500 in the past few weeks to stock into my new 1/4 acre pond. No problems with mortality last summer. It does have a heavy plankton bloom compared to the two 1/4 acre ponds. It's in all clay and holds like a tub. I put in plastic flower pots strung on a rope for spawning.
See the attached Google Earth pic. The pond I renovated in Aug 2015 and the minnow pond show in the pic. The new pond is highlighted in blue.
