Spawn Creek fencing and restoration project
Streamside Incubators: Disinfecting and Treatment for Fungus
Incubators, whether the 'ole frige' or Coleman cooler type, should be diseinfected annually, and/or upon each subsequent usage with new eggs. This also includes "new" units to be used for the first time.
Prior to use, Whitlock-Vibert boxes (WVB), should be disinfected with a solution of 10% Clorox bleach. The WVB's can be placed into a bucket or other appropriate container, with the 10% bleach solution, and left for one hour, and then air-dried. Do not use the Clorox bleach treatment in the incubator units.
The WVB's can also be disinfected by placing them inside the incubator and treating with a 37% formaldehyde solution. This will disinfect both the incubator as well as the WVB's before use. All incubator units should be disinfected before their use with the formaldehyde solution. Treatment by this method is described as follows.
Incubators of the "old frige" type should be disinfected before any use, or they may need to be treated periodically once the eggs are present to prevent the spread of fungus developing on green or eyed eggs. Fungus usually begins to become prevalent about 10 days after eggs are placed in the frige in
Whitlock-Vibert (WVB) boxes. Formalin, a natural biodegradable ingredient, is used to disinfect the eggs. The use of the "new" upweller egg bottles in the incubator units may lessen the ability of fungus to develop as the eggs are in continuous swirling motion. However, some units may have both the WVB's and the upweller
bottle(s) present, hence the WVB eggs may develop a fungus which necessitates a treatment.
For a typical frige, with a volume-size of about 4-feet long by 2-feet wide by 6-inches high will require a 300-milliliter (ml) volume of 37% formalin for 10 minutes. Corresponding treatment of Coleman coolers will be somewhat less depending on the size, from 150-ml to about 75-ml, but the same procedure, as outlined below, is followed.
Immediately prior to pouring the dosage into the frige, turn off the water inlet valve to stop water inflow into the incubation chamber. Pour the 300-ml volume into the frige at the inlet flow entry channel of the incubator. It is suggested to add a few drops of some food coloring (i.e. red, green, etc.) so the flow of the solution can be tracked to assure it becomes well dispersed throughout the incubator, from inflow to outflow.
After 10 minutes, reopen the inlet water valve so water again begins to flow into the incubation chamber. Place a bucket under the outlet pipe to collect the formalin solution, and discard it after all the "colored" solution has passed through the outlet. Or with the outlet pipe or hose allow the solution to drain to the ground adjacent to the stream.
If fungus appears to be continuing, repeat this procedure every 7 days thereafter, or as necessary to assure fungus does not reappear.
Updated: 5/5/2002, Fred Eales, DVM, Flaming Gorge-Lower Green River Chapter, Trout Unlimited
Don Duff, FS/TU National Partnership Coordinator
This page last updated on 11/29/2007