As lake stewards, we often get asked, “Does my lake need lime?” It’s a two-part answer, depending on your focus and importance on the lake’s fishery. If you are not prioritizing the fishery, then you don’t need to invest in lime. However, if keeping a healthy and growing fishery is important, then annual lake checks are needed to determine if the water chemistry is at the desired level.
Agricultural limestone, or lime as it’s commonly called, plays an important role in adjusting the water chemistry to create ideal conditions for phytoplankton production which is a necessity in managing the fishery. Phytoplankton, which are microscopic plants, make up the base of the food chain in a fish population. An abundant phytoplankton base often makes lake water appear green. When phytoplankton is maintained at a balanced density, often through fertilizer applications, the carrying capacity (the poundage of fish that the lake can support) can be doubled to tripled.
Not every lake with a managed fishery in this region of Georgia needs lime but most of them do. The determining factors are the hardness and alkalinity levels. These levels are measured in parts per million (ppm) and most lakes in this region average around 8-16 ppm on both parameters. We like to get these levels to 20 ppm and higher to create the ideal conditions for phytoplankton to be successful. A simple water test determines these levels. Generally, anywhere from 1-5 tons of lime per surface acre is needed to raise the levels depending on how low they are to start with.
For the process of liming, there are two methods: dry lime and liquid lime. Dry lime can be delivered in bulk on a dump truck, placed next to the lake, then loaded on a lime barge with heavy equipment. Then the lime is sprayed off the barge in a slurry to sink to the lake bottom. If the lake is small or the access is limited to prevent a large barge and heavy equipment from coming in, then liquid lime is a good option. Liquid lime is a bottled version of highly concentrated lime. Like dry lime, the liquid is spread over the entire surface of the lake. For the application of liquid lime, since no heavy machinery is required nor a heavy-duty boat, the costs of application are much lower.
Lime benefits tend to last from 2-5 years before a reapplication is needed, however, the benefit could last longer. A simple check of the hardness and alkalinity would determine when it is needed again. The benefits of dry lime applications tend to last longer than liquid lime, but liquid lime tends to require a lower investment cost
If you want to invest in your fishery or have been and aren’t seeing the benefits with fertilizing, call our Fishery team at Aquascape Environmental to perform a simple water test to see if you need lime. Then if lime is required, there are good options to accomplish the task no matter what your lake access is like.
Article written by: Matt Troxler – Lake Operations Manager – Fisheries Biologist
