I would like to talk about insects.  Specifically, grain beetles.  If you are like us and have been feeding fish for a long time, then you’ve seen a bug or two – or more!  The fact is bugs are a part of our lives even if we do not like them.  On occasion, I have even picked up dog and cat food from the grocery store with bugs!  Grain beetles are also known as pantry beetles because they will show up in your flour, corn meal, rice, pasta, and even dry beans!  Fish feeds contain grains, so it just stands to reason those bugs are going to end up in it.  Another little flitter critter to look out for is the meal moth.  The larvae of these moths will make silky webs in the feed.  I know, so strange. 

There is something about late summer that makes these bugs infest just about everything.  High humidity is a likely cause, but we really just don’t know what it is.  In the South, it's always difficult keeping the infestations at bay.  It’s been wet, humid, and extremely hot this year, and I expect to see a few bugs!

US Fish Feed Manufacturers and Distributors are expected to follow certain Regulatory Guidelines when producing and storing aquaculture feed, which would include certain types of pest control. Complete fumigation of large processing plants and warehouses containing foods for human and animal consumption is not considered a safe practice under these guidelines. 

The Typical Scenario of the Warehouse Fight Against the Bugs:

We start out in late winter/early spring with the first round of fish feed productions.  We use the same treated grains (wheat, corn, soybeans) that are used in the production of human foods.  The feed mills have been down for a month or two, and the crews have had time to perform routine maintenance and hopper cleanouts.  It is also likely that a winter freeze has killed existing grain insects throughout the mill.  By early summer, the mills are in full production and the  crews are barely keeping up with the orders and machinery repairs become more important than hopper cleanouts. So, while that feed is setting there in the hopper, all it will take is one little beetle to lay hundreds of eggs, which will hatch into tiny little white squiggly wormy larvae that (to me) are grosser than the beetles!  Within a few days, the larvae become full grown beetles, and the infestation has begun!  So, let’s just say the crews go ahead and begin the hopper cleanouts and each production is a fresh batch of bug-free fish food.  Well, if just one of those icky bugs or larvae escaped from the hopper (and you know they did!), where do you think they will migrate to?  Of course, that fresh new feed that was just made!  The feed then gets bagged and sealed, sold, shipped, and then placed in someone’s storage building, garage, or even home pantry!  If that feed isn’t used within a couple of weeks, it is likely to become infested, along with everything else nearby.  Many people think the products must be old or out-of-date when the insects appear, but that simply is not always the case because the complete lifecycle of these insects is literally just weeks!

So, what do we do?  There are a couple of things you can do when you see bugs in the feed.  We already know that the bugs can’t live in sub-freezing temperature.  Many pond owners freeze the fish food in freezer baggies and take out only what is needed at feeding time.  This would work if you have access to a large freezer, and if you don’t mind keeping fish feed next to human food. LOL! 

I personally use Food-Grade Diatomaceous Earth.  Most everyone is probably somewhat familiar with this product, as it has been around for a long time.  Us old timers have been using it for years! It kills insects by cutting their little buggy bodies and basically drying them up.  It is not an insecticide.  Many farmers use it in animal feeds for various health reasons, one being that it kills parasites and worms. It is not harmful to animals or fish.  Just bugs.  In fact, once the product becomes wet, it becomes ineffective.  This product is also known as Bentonite and Montmorillonite Clay.  Some feed manufacturers actually process these products into the formulation because it is good for the pond water.  I prefer the white Diatomaceous Earth over the other two.  It seems to work faster.  I add about 1/2 lb of Food Grade Diatomaceous Earth to 25 lbs of feed and mix it up in a storage tub and cover it with the lid.  Within a couple of days, both larvae and crawling insects will be dead. This also works on ants, and any other crawling insect - as long as the Diatomaceous Earth remains dry.  None of these products will harm wildlife or pond water.  The only drawback is that it will make the feed pellets present a light or white coating.  No problem, as long as you know what it is, right!

Of course, another option is do nothing.  That’s right.  There are many fish hobbyists out there who think the bugs give them some additional protein and feel there is no need to worry over it. In fact, the larvae of the red flour beetle is considered a treat for young koi and goldfish!  I definitely recommend using it up as quickly as possible if you go this route.  Just like all of God’s creatures, bugs excrete what they eat, and that is also in the fish feed.  

Bottom line is that the fish don’t really care.  They don’t care if the feed has been frozen, covered in Diatomaceous Earth, or infested with wigglers and bugs - and their buggy poop!

But, we love and care about all of our pets.  Whether you are keeping food fish or ornamental fish, it is best to keep the food you feed them as healthy as possible. Do not by any means ever spray insecticide on your fish feed or any pet feed, not even bird seed. It is healthier for animals to eat bugs than be exposed to insecticide. 

As always, we suggest storing your fish feed in an airtight container - dry and not exposed to heat or moisture. Keep one of those inexpensive tubs with a lid around so you can mix in some Diatomaceous Earth, if needed. 

Questions and Comments?  We would love to hear how others deal with this issue!