Oct 5, 2012 – Fleas And Fish


I have a new customer with a flea problem at a newly aquired live bait shop. The previous owner had a dog living in the shop but no pets are currently present. My concern is the 7 large bait tanks. They are open air and are aerated 24-7 with an on site, indoor electric air pump. One pump aerates all tanks. I treated attached offices and restrooms but am very leary of applying any insecticide directly in the showroom where tanks are located (and owner claims bites). Is there a relatively safe treatment for this area? I did have them turn off the A/C while I treated offices to stop air movement but they can't shut down the aerator.


Something you mention tells me that YOU are not convinced there is still a flea problem here, as you state that the owner "claims" he is getting bitten. Just in case my thought is correct, perhaps it is a good time to set out a lot of insect glue traps and inspect them in a few days to see what is caught. Perhaps the flea infestation is actually eliminated but the owner still feels the paranoia of the problem that used to be there.

If there still is an ongoing flea presence then you are correct in being concerned about the use of insecticides where air pumps could suck some of the aerosolized particles into the tanks. Obviously a very careful application should prevent this from happening if you use low pressure and a larger orifice on the spray nozzle, but even then if a few fish turned belly up in the next few days you would be blamed. Many product labels will even instruct or suggest that air pumps to aquariums be shut off prior to an application just as a precaution. One product that you should be able to use without concern for fish, although you still need to take extra measures to ensure no mist enters the air, would be an IGR such as Precor. Since the IGR is identical in nature to normal hormones in the system of insects, and not fish, even if some of the IGR somehow ended up in the tanks it should not have any effect on the fish. The IGRs do not kill adult fleas, but along with non-chemical approaches such as a very thorough vacuuming of carpets and all edges of hard floors it will stop any further development of adult fleas.

Without any more pets in this shop the flea problem will, eventually, disappear by itself, but I'm sure the owner would prefer that they are gone immediately so that he can quit feeling the sensation of bites. If the fleas really are still present then it would be either flea pupae that have not yet hatched to the adult stage or lingering larvae still feeding on debris in places where they can find it. Open expanses of hard flooring are not likely places to find flea larvae or pupae, so there would be no reason to spray those surfaces. If there are carpeted areas in the shop itself these need to be very thoroughly vacuumed.......repeatedly, and every day for the next week. This is good advice whether or not you even spray any insecticide, as it causes flea pupae to immediately move to the adult stage where they may be vacuumed or otherwise killed.

For hard surface floors there could be an accumulation of dog hairs and other debris, including those dried blood fecal pellets of the former adult fleas that are a dietary requirement of flea larvae. The vacuuming, using a high power vacuum and a narrow tip, should concentrate on removing all of this accumulated debris. Washing the floor with a good cleaner should also help, and even wash down into the crevices to affect any flea stages in them. But, begin by ensuring you still have a flea problem there and not the customer's imagination. Then do the intense cleaning and perhaps apply an IGR to carpeted areas and crevices where you might expect flea larvae still to be present. Strongly recommend the continued vacuuming daily for the next week.

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