Bait Tanks

Key Questions:

If you are considering purchase of a bait tank or perhaps making one yourself, here are some important questions to answer first:

What kinds of baits?

The type and size of baits you will use should dictate the size of your tank in addition to needs related to water recirculation, aeration, filtration, tank insulation, and tank fittings.

How many baits and storage duration?

The number of baits your tank must hold and the duration you will store them will also impact the same issues as the kinds of baits you will place into your tank.

When and where will you fish?

If you fish in the heat of summer or in any warm location, you will need an insulated tank, a cooling strategy, and/ or varied aeration options. If you are fishing in a small boat, that can impact the capacity, height, power source, and shape of the tank you want. Similarly, if you fish primarily from the bank or dock, the size of the tank, mobility and power options must all be considered.

How often will you use your tank and what is your tank budget?

Your tank budget will likely depend on whether you fish several times each week throughout the year versus less frequently or mainly in the fall, winter, or spring. How you should handle issues like insulation, filtration, aeration, and tank construction materials can vary based on the answer to this question.

What options do you have for purchase or construction of the tank you need?

If you live in an area where there is good potential to buy a used tank to meet your needs, you will want to explore that option before buying a new tank. Whether used, new, or DIY, shipping costs for tanks can be a significant portion of the total tank cost. You will want to factor possible shipping costs into your decisions.

 Tank Features:

After you have answered the basic questions about your future tank, you will want to consider details about the tank’s features.

Tank size

The tank size needed should be based on the number, type, and size of baits you need to hold in your tank. Use this chart as a guide assuming you will store baits on the day you fish and assuming your tank water is properly treated and cool with good oxygenation.

Bake Type / Size                                                       Capacity Allowance

Herring/ alewife (less than 7 inches)                   two dozen per 10 gallons

Shad (less than six inches)                                  two dozen per 10 gallons

Shad  (5 to 10 inches)                                          one dozen per 10 gallons

Small brim or sunfish                                            one dozen per 20 gallons

Pilchards                                                                  8 lbs per 10 gallons

Large minnows                                                    three dozen per 10 gallons

Sardines (greater than 5 inches)                             five per 10 gallons

Sardines (less than 5 inches)                                  15 per 10 gallons

Medium minnows                                                 five dozen per 10 gallons

Small minnows                                                     eight dozen per 10 gallons

Chubs                                                                    1 1/2 dozen per 10 gallons

Crabs                                                                    two dozen per 10 gallons

Shrimp                                                                  four dozen per 10 gallons

Baby catfish                                                           1 pound per 10 gallons

Trout (less than 4 inches)                                    one dozen for 10 gallons

Trout (4 to 7 inches)                                            one dozen per 20 gallons

 Tank Shape

If your baits are herring, alewife, shad, trout, brim or sardines, you will want a round or elliptical tank or a tank in which corners are rounded. These baits often swim rapidly around the tank and can injure themselves by swimming into corners.

The shape of the tank including its height can also impact where you can place it in a boat, cart or dock and the floor space required.

Color

Although white is the most common tank color, studies have shown that blue and green interiors can have a calming effect on tiddlers.

 Insulation

The amount of oxygen that is dissolved in water is heavily dependent on water temperature. The level of oxygen dissolved in your tank water and the temperature dictate how long your bait will last in your tank, how many baits you can keep alive, and how lively the baits are. If you fish extensively in the summer with a tank heavily loaded with baits, you should consider an insulated tank or using an oxygen tank to aerate and cool your tank. Otherwise, blue ice blocks or frozen coke bottles can provide an alternative to insulation. If you plan to add ice directly to your tank, make sure it has no chemicals such as fluorides or chlorides in it.

Aeration

The purpose of aeration is to add to or maintain the oxygen level in your bait tank water to keep your baits alive and lively. Aerators also assist in removal of ammonia and other unwanted gases through water agitation. Options include:

No aeration works for a moderate amount of smaller minnows for a day or night of fishing. However, aeration of some sort will extend bait life, tank capacity, and friskiness.

Bubblers with air stones are effective for most baits if the air volumes produced are sufficient. They do not produce significant water circulation and usually are used for smaller, slower moving baits. Compared to other aeration options, bubblers typically require more power to provide a specific level of aeration. However, bubblers can be powered easily from small batteries or USB power packs. This makes them an obvious choice for bank/ shore fishing and tanks in a mobile fishing cart. Like venturi aerators, bubblers tend to drive water temperature to the temperature of the ambient air. This can be a problem in the summer heat.

Venturi aerators are common in tanks, 10 gallons and above, where there is power for a recirculation pump. Water from the recirc pump flows through a venturi which sucks air from outside of the tank and mixes it with the tank water. Venturi aerators are generally considered capable of adding the most oxygen for the amount of power consumed beyond recirculation. However, like bubblers, they add heat to the water in the summer. When only one pump is used for recirculation and aeration, turn down of the pump for recirculation impacts addition of oxygen into the tank water.

Agitators have spinning paddles operated by a small motor. The paddles mix air with the tank water. Agitators are normally used in tanks 20 gallons or smaller. They also add heat into the water on warm days.

Spray bars are pipes with holes in them. A pump pushes tank water through the spray holes above the water line in the tank. This mixes air into the water to oxygenate the water. The recirculation current in the tank when using spray bars is minimal such that a second pump is sometimes required for recirculation.  Compared to the amount of power consumed, the amount of oxygen added to the water is less than a venturi aerator. However, when the ambient air is dry, the spray bars do have a small cooling effect like an evaporative cooling tower.

 Oxygen tanks are the most efficient means of oxygenating your tank water. However, the cost of the tank, tank mounts, controls and air stones add to the ongoing cost of oxygen tank refills.  When the heat added to the boat bait tank is excessive in the summer because of other aeration methods, this aeration approach excels especially for baits like blueback herring, shad, alewife,  etc.

 Filtration

Filters remove scales, fish turds, bio waste, and other debris from the tank water. Typically, a pump sucks water with debris from the bottom of the tank and through the filter prior to moving the filtered water through the pumps impeller. Optionally, the water is then pumped through a venturi aerator or spray bars prior to recirculating the filtered water around the tank. Filtration options include:

Filter pads and flosses are the most common filters used in mobile bait tanks. Unfiltered water is drawn up above the pads or flosses where it flows down through the filtration media before recirculation. Other similar configurations include filter boxes in which the dirty water is either sucked or forced horizontally through pads or filter floss.

The pads or flosses are washed or replaced when blinded with debris.

This filtration approach consumes considerable tank space but it is simple and dependable for baits like shad that produce significant waste. Pads like koi ultra filters last longer than a year and are easily cleaned.

 Filter socks are also used for baits that produce significant waste or for longer term bait storage. Flow through the socks is similar to that described for pads. Socks are washable and renewable. Some people believe that socks are easier to rejuvenate than pads but that is debatable. Various other filter media are sometimes used in conjunction with pads or socks especially when baits are in the tank for longer periods.

Mechanical filters frequently with washable cartridges are useful in portable bait tanks when the baits do not produce significant waste or when baits are not stored in the tank over multiple days.

The cartridges are easily removed, cleaned, and replaced but require cleaning more frequently than pads or socks. Because the filtration surfaces are smaller than pads or socks, mechanical filters require less tank space.

 Pumps

Pumps and portable bait tanks usually drive the water plant which may filter tank water before passing it through the aeration process prior to recirculation within the tank. When a single pump is used, the pumps are typically capable of 100 to 250 gallons per hour (GPH) in tank capacities of 10 gallons or less.  Pump throughputs of 220 to 500 GPH are usually found in tanks holding 10 to 25 gallons. Multiple pumps and/ or larger pumps up to 1100 GPH come in larger tanks. Frequently, bilge pumps are used in bait tanks although some tank configurations require pumps designed for boat live wells.

Tank fittings

Fittings include drains, doors, hinges, handles and the like. Drains are helpful in emptying a heavy tank after use and for partial water change outs. If a tank will be moved frequently, carry handles are quite useful. Regardless, all fittings should be made of plastic or stainless steel to avoid corrosion contamination and for long life.

Lights

Interior lights are a great feature on tanks used frequently for night fishing. Regardless of how they are configured, waterproof LED lights are required. Many believe that a light off switch is helpful when the bait door is closed to keep the bait calm.

 Power supplies

Power supplies include the tank’s power wiring, connectors, and batteries. Tanks used in boats typically rely on batteries mounted in the boat. Alligator clips sometimes connect the tank wiring directly to a battery. To eliminate issues with the path of the tank power wiring, connectors like lighter plugs, SAE plugs, etc connect the tank to boat power outlets. To preserve the boat battery, some people connect the tank power connector to a 120 volt adapter when bait is kept overnight.

Tanks with pumps that are used in a cart for bank or surf fishing require a small deep cycle or rechargeable battery of sufficient capacity for each outing. Tanks without pumps that utilize bubblers can use a similar battery or a USB power block to power the bubbler.

 Controls

Tank controls, at a minimum, should include a fuse for the power wiring. Flow valves or variable speed pump controls are helpful to adjust recirculation flows for different types of baits or bait loadings. As noted previously, switches for lights are helpful. A water temperature indicator is good to know that tank water is within acceptable ranges. A temperature alarm is even better to prompt corrective actions like addition of freeze blocks in the summer.