Pond liners aren’t optional for algae ponds. While you may be able to grow fish or plants in mud-bottomed or clay-lined ponds, this won’t work for commercial algae production. First, the presence of mud or dirt in the pond will lead to extremely turbid water due to the need for constant mixing. All the debris that is stirred up from the bottom obscures light transmission, causing your algae to grow slowly or die-off entirely. Second, natural bottom ponds are also very difficult to harvest from with commercial scale equipment. Unless you only plan to scoop off a little algae here and there with a net, you’ll need a liner to protect the pond’s bottom and walls from harvesting damage. Finally, pond liners are also the only way to have any control over contamination or water quality when using outdoor open ponds.
Allowing for Effective Harvests
A flexible pond liner offers the most effective harvesting techniques. Whether you plan to skim the algae out of the water, treat it with a flocculant to cause it to settle on the bottom, or have some other method, a clear barrier at the bottom of the pond allows for a full harvest. There’s no need to lose 10-30% of the total algae as it mixes with mud or muck from the bottom of the pond. Even seaweed is easier to harvest in a lined pond and tends to grow back faster after trimming.
Simplifying Pond Maintenance and Cleaning
When it comes time to clean out any dead algae or accumulated debris at the end of a growing cycle, lined ponds are far easier to vacuum or sweep than unlined ones. Natural ponds don’t have a clear barrier between the muck of the pond and the mud below, making it likely you’ll cause a leak to start even with basic cleaning and harvesting techniques. Flexible liners from BTL Liners are tough enough to withstand poking with a net or vacuum tool without ripping or tearing. Even concrete or stacked rock liners make it easier to maintain an algae pond, but they can’t be cleaned of unwanted algae growth as easily as geomembranes.
Preventing Growth of Unwanted Organisms
While spores, bacteria, and other contaminants can land on the surface of open algae ponds, they’re still less likely to settle in if there’s a liner in place. A muddy bottom surface creates more opportunity for unwanted algae, plants, and bacteria to settle and make a competing colony that threatens your algae growth. Lined ponds are easier to keep clean and maintain and also can keep unwanted invaders from moving in.
Controlling Water Loss and Entry
If you’re trying to maintain a specific salinity or pH level to encourage growth of just one specific type of algae, you need to maintain a steady body of water as much as possible. Reducing water loss through seepage into the ground is as easy as installing a flexible and impermeable geomembrane liner. Concrete liners reduce water loss to a certain extent, but they quickly form micro-cracks that cause a surprising amount of seepage. Impermeable liners won’t crack for years to come and offer better control of water loss. They also stop water from entering the pond from the surrounding soil and diluting your current balance of salt and minerals.
Pairing with Concrete and Other Liners
If you do want a concrete liner for an algae pond to reinforce weak soils or increase total volume, consider pairing it with a geomembrane as an underlayment. As explained above, concrete doesn’t remain impermeable for very long. Any little shift in the soil below can leave the material cracked and leaking. Concrete itself is also somewhat permeable due to tiny pores that let water soak out slowly similar to a sponge. Additionally, many products available to spray and seal the surface aren’t safe for algae production, especially for food.
A flexible geomembrane liner is the best way to seal an algae pond quickly and permanently. Whether you’re using a concrete liner or not, flexible membranes are easy to install and need little maintenance over the years. Explore our products here at BTL Liners, including our reinforced polyethylene (RPE) liner ArmorPro, to find the right material for your algae ponds.
