Liners are important elements for any ponds in your aquaculture setup, but they are particularly critical for nursery ponds, where the greatest care must be taken to avoid damage or degradation over the course of many years of use.
The fry-to-fingerling stage of growth is the most critical in an aquaculture operation. In this stage, the fish are at their most vulnerable to predation, to temperature variations, water quality issues, etc. It makes sense to ensure that nursery ponds are built with the best materials since scrimping on this stage will have a huge impact on the health and size of your yield.
Whether your aquatic nurseries are actually above ground tanks or in-ground ponds, they should be lined with an impermeable liner. The first reason seems fairly obvious: any kind of leak in a nursery pond can be disastrous, especially if you’re maximizing your stocking rate. In these cases, crossing over your maximum density can quickly deplete dissolved oxygen and leave you with mass casualties in an extremely short period of time.
Fry and young juveniles need to be kept in as pristine an environment as possible. Invasive weeds, predatory insects, and any number of parasites or diseases present huge problems if they’re uncontrolled. Regular cleanouts are pretty much obligatory, and seasonal ponds with a complete annual dry out are an excellent way to manage or eliminate all these problems with minimal use of chemicals. Regardless of which method you choose, your selection of pond liner plays a big role in the success of your operation.
You’ll need an impermeable liner that’s strong and durable, resistant to tears and punctures, easy to install, and preferably, one that can be installed in a single panel, without the need for seams. Your liner will need to be resistant to UV degradation, especially if it will spend weeks exposed to the direct sun, as in a seasonal pond. It’s hard to imagine a bigger disaster than getting ready to stock your nursery pond and finding that your liner has grown brittle from sunlight and is now shredding with every touch.
Your pond liner should be safe for fish and plants. If you’re producing for an organic market, you’ll need to go a step further and ensure that your liner is certified for food grade use. Some liner materials are known to leak plasticizers and other chemicals that can injure or kill fish. It’s easy to listen to conventional wisdom and the voice of random experience that says a random liner “never hurt any of my fish,” but when you have such a delicate, valuable population - it’s not worth the risk of relying on word of mouth.
Reinforced polyethylene (RPE) is a great investment for the exacting needs of a nursery pond. It is lightweight, easy to install, and can be manufactured in very large single panels so that seams are not required. RPE’s reinforcing scrim layer prevents both tears and punctures, and the qualities of polyethylene (HDPE and LDPE) make the material naturally resistant to UV exposure. BTL Liners’ AquaArmor products are not only safe for fish and plants, but are certified for containing potable water (intended for human consumption), which is the highest level of safety available. A high quality liner like this is suitable for years and years of use and will stand up to the wear and tear of pond maintenance, sun exposure, etc. Give BTL Liners a call and we’ll be happy to work with you to select the best product for your operation, answer questions, and draw up a free quote for you!
