Pond Boss Forums AERATION Systems questions System broke! O2 problems

I doubt that the Vertex system was destratifying the entire lake. Only oxygen tests in several depth profiles would prove the completenes of the mixing.
Destratification will occur fairly rapidly. With in several days depending on wind exposure and surface weather. Small ponds and even swimming pools can stratify within 24 hours. However the rate of oxygen loss is dependant on the fertility of the system. If you have been fertilizing or the lake is nutrient rich then oxygen loss at the bottom can occur in about two to three days. Oxygen loss creeps up from the bottom toward the bottom on the thermocline. This rate of DO loss is also dependant on how fertile the system is and how much "rainout " of dead phytoplankton/zooplankton/organics is occcuring. Bacteria densities are abundant in water with 24" visibility. Bacteria are the main oxygen consumers and they can quickly increase in ponds when the amount of organics increase. My guess in a week things should start to deterioate in the deep zone. However your top layer (epilimnion) should remain oxygenated and you should not lose fish. Your fish will move up to the oxygenated zone; they will find the water with DO. You will only have a problem if in four or five weeks you get a rapid turnover and then you may lose some fish.