Grit Blogs > Life and Adventures at Diamond W Ranch

Goldfish for Mosquito Control in Stock Tanks

By Jacqueline Wilt, R.N., C.E.M.T.


Tags: Livestock care, mosquito control, stock tanks, livestock watering, west nile virus, zika virus, Jacqueline Wilt, Kansas,

Life and Adventures at Diamond W RanchThe mosquitoes are terrible around our area this year. With the threat of West Nile Virus and Zika Virus lurking in the news and coming across my desk as a health department nurse, I am doing my best to be vigilant in protecting my family (and my animals) from getting bitten.

However, another thing we can do as livestock producers is to try to reduce the availability of breeding grounds for mosquitoes. Mosquitoes must have still or stagnant water in which to lay their eggs. Common areas around the home are flower pots, old tires, buckets, animal water bowls, tarps or swimming pool covers, and livestock tanks. It is fairly easy to control standing water in most of these items, but dumping and refilling large stock tanks is a big chore, and not very easy to maintain, especially since mosquitoes can go from egg to adult in less than a week.

The solution I have found is to employ goldfish. Goldfish are wonderful tank cleaners! They keep my tanks cleaner longer and they eat mosquito larvae! Every summer I go to the pet store and purchase a bunch of feeder goldfish, which are usually less than 20 cents each. I divide them among my livestock tanks and let them work all summer. The tanks I have are mosquito-larvae free!

Goldfish employees ready for work

I did this earlier this year, about a month ago. But I only purchased about 15 goldfish, and put them in two of my four stock tanks. The two tanks with goldfish were completely free of ANY mosquito larvae. The other two were disgustingly (and literally) SWIMMING with the little blood-suckers-to-be. I quickly went back to the pet store and purchased 30 more goldfish and divided them into the other two tanks. For less than $6.00, I have mosquito control all summer long. And, within 24 hours, the goldfish have the tanks almost 100% free from mosquito larvae already!

Goldfish into the tank

I do not have to feed the goldfish anything additional, they sustain themselves fine on what gets into the tanks. The tanks are still cleaned about every 3-4 weeks. When I clean them, I scoop some of the tank water into a bucket, dump the tank, rescue the goldfish and put them into the bucket while I clean the tank. I have never lost a goldfish doing it this way, except once, when one of the chickens beat me to one of my fishy employees.

The goldfish are an inexpensive, efficient, fun, and chemical-free way to keep my stock tanks cleaner and healthier for my animals.

Goldfish getting to work

Have any of you ever used goldfish in your stock tanks? What other ways do you control mosquitoes in your stock tanks?