Besides the obvious charm and enjoyment water containers provide, there is still some maintenance involved in keeping them attractive and running properly. Along with general cleaning duties, protecting your water container fish and plants from insects and pests can seem like a full time job. To name a few: aphids, mosquitoes, spider mites, midges and moths are some pests that can affect the well-being of your water garden. Luckily, just having fish in your containers can help keep the problem under control. Simply hose the insects into the container and viola, fish food.
If you’re trying to avoid using chemicals to aid your efforts, there are some organic methods of fighting off insects and pests. A salt-like white substance called Diacetemous earth (found at swimming pool suppliers) can be placed in a salt shaker and then sprinkled over the affected area, where its tiny points puncture invaders and eventually kill them. Bacillus Thuringiensis (“Bt”), found at garden supply stores, is a bacterium that, when in direct contact with insects, will parasitize its digestive tract and kill it. Because this bacterium comes in a powder form, it can get messy so try mixing it with water and spraying it directly onto the affected areas.
For the control of aphids, try mixing a small amount of dishwashing detergent along with vegetable oil and water in a spray bottle. The detergent will help the vegetable oil mix with the water while the oil suffocates the aphids. Once the aphids are dead, remove the oil simply by flooding the container so as to prevent oxygen deprivation for the fish.
Although Spider mites are not common in larger water containers, they can be found as some sites. A simple hosing on a daily basis with a strong water jet will usually keep them at bay. For especially bad infestations, remove all plants and hose them off so as to remove any eggs and nymphs from underneath the leaves. Insecticidal soap can also be used every three days underneath the leaves to control the problem.
Mosquitoes are known to breed in the smallest puddle of standing water so it shouldn’t be a surprise to find them living in your water container. However, that fact doesn’t make them any less annoying. Again, in this case you may luck out if you are keeping fish in your container because mosquito larvae are a tasty snack for fish. If your container is sans fish, try floating donut-shaped Mosquito Dunks in your container for mosquito control. For smaller containers, try breaking off a small piece from the donut to float in your container. Mosquito Dunks contain Bacillus Thuringiensis (a bacterium mentioned earlier that parasitizes the digestive tracts of insects, killing them) and are completely natural and will not harm your fish, pets or people.