How do you know how many bait fish you can keep alive in your bait tank?
There are a number of bait keeping factors to consider, as well as several
methods for calculating stocking levels.
- 1 inch per gallon rule ( Most
often recommend by biologist )
- Example: 1000 gal tank 8 inch shad = 125
- 5 inch shad = 200
- Surface Area Calculation
- Weight per volume of water (1oz. to 1 gallon).
- Fish length to filter capacity.
One Inch Per Gallon Rule.
The most widely recommend rule for stocking a tank is one inch of fish per gallon of water.
While this works as a rough estimate, it leaves room for error. Fish
are not all the same size and shape. Stocking a 50 gallon tank with 50 inches of slender
minnows is not the same as stocking it with 50
inches of just caught 8 inch shad and each method will be influenced by how long your fish will stay in the tank
along with other perimeters.
Also when you first capture shad they create a lot of waste, and therefore require more water volume. So while the one-inch per gallon rule is a good guide, it has it's drawbacks
when shad are first stocked into the tank.
When I stock a fresh load of shad into my 1000 gallon holding tanks the
number will depend on the time of year, the temperature of the air as well as the temperature of the water in the holding tank and the water
temperature where I caught them from and how far they were hauled.
Surface Area Calculation.
Fish length to surface area (1" of fish for every 12 sq.
in. of surface).
The larger the surface area of the water, the greater the oxygen exchange,
which in turns supports a larger number of fish. Therefore, surface area of
the water directly impacts how many fish can be kept in a tank. A tank that
is tall and thin may hold the same number of gallons as a tank that is short
and wide, yet they have vastly different surface areas.
The surface area is calculated by multiplying the width times the length of
the tank. Under the water surface area rule the tank can be stocked with one
inch of fish for each twelve square inches of surface area. However, this
calculation has many of the same flaws as the one-inch rule. For instance,
it assumes a fairly slender fish, which isn't always the case. If
wide-bodied fish will be kept in the tank, the calculation should be changed
to one inch of fish for each twenty inches of surface area.
Like the one-inch rule, the surface area rule isn't perfect. Its primary
advantage is that it takes into account unusually shaped tanks.
Some of the bait keeping factors are:
How much waste can your
filter system process.
- Different filter types and different brands and models will be able to
process different densities of fish waste. Power filters, even those
with an attached rotating drum filter, just cannot handle the volume of
fish waste and decomposing organic matter that a well maintained under
gravel filter can handle, and an under gravel filter can only handle a
fraction of what a good wet-dry or trickle filter can handle. Canister
filters will typically handle more waste than a power filter, but rarely
as much as a trickle filter, and the capacity of these filters varies
greatly depending on the make and model of the canister filter, as well
as the media used in the filter.
- The ability of the water to dissipate the waste as
the fish release it.
- A larger tank will keep the water cleaner, without regard for the
filtration system in use.
Coupling this with a good filter system and regular water changes will
improve your fishes' health and heartiness.
- Dissolved oxygen available in the water.
- The greater the surface area, the greater the holding capacity of the
Any filter that will disturb the surface of the water, such as power
filters or most canister filters, will therefore increase the
theoretical load of the tank, provided that the filters have a good flow
rate and are sufficient for the size of tank in question. A trickle filter will provide massive increases in surface area in the
water, getting the solution of atmospheric gases in the water closer to
the proportions in the air in the room.
biological filter also requires oxygen to function, so your biological
filter will often be more efficient in a well aerated tank, but a fair
portion of the oxygen dissolved in the water may be taken up by the
filter, and not really leave any extra for additional fish.
However, even multiple filters on your tank may not greatly increase the
holding capacity of the tank.
- Good maintenance:
- The maintenance provided to the tank and the equipment can greatly
influence the tank capacity.
Regular, frequent, small water changes, filter cleaning and filter
cartridge replacement (if necessary), cannot increase the capacity of
the tank, but failing to do this will certainly decrease the capacity.
- Size of the fish when compared to the dimensions of the
- When you are calculating capacity of your tank, consider
the size of the shad you will be keeping.
Overpopulation in a tank will lead to or contribute to many problems.
- An overpopulated tank will require greater
maintenance, and fish waste builds up faster and the filter gets
- An overpopulated tank will frequently produce more
waste than the filter can efficiently process, allowing the waste in
the tank to build to potentially toxic levels, even if the filter is