Pond Boss Forums POND CONSTRUCTION Creating habitat Draining pond cause us to lose plankton

We are filling a 5 acre pond up right now to test out the dam, spillway, pipes and figure out the ideal level to leave it at. we added structure but not enough since we were in a time crunch. I have not added any fish yet. I was planning to let it fill up and hunt it and then drop it down in Feb. to add structure and do maintenance then fill it back up before we add fish. There is no rush on fish so i could wait til next year. Would my plankton die off? would i be going backwards

I don't think that will be a problem at all. Are you going to completely drain or just drop enough to add the structure? When do you plan to add fish? How long do you expect it to fill after you drop the level?

If you leave some water in the pond after drawdown the plankton will persist at reduced numbers and then quickly regenerate in several weeks upon refilling.

One caveat about waiting to stock fish. If there are any ponds above in the watershed or streams nearby that the possibility exists that some trash fish get in the pond before it gets stocked the trash fish can multiply and really mess up a stocking plan.

If you are going to wait a year before stocking, just be sure there is no possibility of fish being accidentally introduced ahead of time (like from "helpful" neighbors).

GSF have messed up more than one stocking plan by getting in early, multiplying, and getting big enough to eat most of the fingerlings stocked. Ending up with a pond full of GSF rather than what was stocked.

Just be aware of the potential.

Pond is fed from a natural creek so no other fish should be able to get in unless a bird brings them in. Pond should take around 3 weeks to fill up depending on rain. I will probably lower it just enough to do the work on the points (adding a foot of dirt) and structure and then raise it back

Natural creek a potential source of fish.


Natural succession can be cause apparent loss of plankton. When I let a fishless pond go for a while, it often clears. Zooplankton causing graze phytoplankton to almost nothing while zooplankton themselves stay deeper as a big giant cookie where light levels are low. Biomass in that cookie can be huge. You need snorkel or SCUBA gear to see cookie. You can sometimes get into by sampling a range of depths that include just above the bottom. Cookie itself sometimes less that a foot thick. Waterfleas dominate cookies I see although phantom midges can get dense as well.

Agreed, sounds like that is a good amount of inflow if a 5 acre pond will fill in 3 weeks. Those pesky green sunfish can live anywhere that has standing water, even just a few inches. Perennial streams with constant above or below ground flow normally have some fish if there is the right habitat. What does the creek look like above the pond?

There are fish in the intermittent stream that flows about 330 feet south of my ponds, even way up the stream on the side of a hill. They are mostly Gambusia and Ozark Minnow, but fish nonetheless. It normally dries to small potholes from August until November, but the fish manage to survive.