A flat bottom tank is a cheaper tank to manufacture as they do not have complicated sumps/ribs etc. They require extra steel on the frame and around the sides to support the thin plastic tank on uneven ground / challenging farm environments.Having excess/unnessary steel in the frame makes it heavier to lift on to the towbar of the atv /utv so you run the risk of hurting your back.The downside of these sprayer tanks is they are made of thinner plastic they require more framework to support them and not strong enough to withstand the use on uneven ground / challenging farm environments, The downside of these sprayer tanks is that they are not very resistant to UV Light /prolonged exposure to sunlight which means your tank will breakdown and crack over time in the bright NZ sunlight.Which means your sprayer won’t last as long and you will have to buy a replacement tank which comes at quite a cost and if you can still buy that type of tank. With a flat bottom tank you cannot fully drain the tank meaning you will always have fluid left in the tank which may be around 5 + litres of chemical in the tank. If you leave it in the shed eg: over the winter time it will build up with mold on the inside of the tank and when you go to use it again that mold etc will end up possibly in the pump. This will do damage to the pump and will incur costs of repairing or replacing the pump which comes at a cost.
On a flat bottom tank if you park on a hill and all the chemical comes to the front of the tank and the suction is at the middle or back of the tank you will not be sucking any spray/chemical ,it will suck in air causing air in the lines and it won’t pump or spray. So this type of sprayer needs to be used only on flat ground or especially for the last 30 ltrs. Finding a flat area on a lifestyle block or farm can sometimes be a challenge. With the trailer able to be only parked in selected flat ground areas you can find your hose may be too short so you can’t reach the places you want to spray in. With the sump option spray tank trailer sprayer they come in a thicker /heavier duty plastic as they have ribs/sumps to make them stronger to withstand the use on uneven ground / challenging farm environments. They do not need so much steel in the framework thus making it easier to lift. These do cost more upfront because of the thicker /stronger tank but have a more robust frame to mount the tank and withstand the everyday farm use . While cost is a significant factor, ensuring the durability/ reliability/longevity of spraying equipment is challenging in farm conditions is paramount.
With a sump tank you can fully drain all the chemical out of your spray tank meaning you will not end up with mold etc in the tank when it sits in the shed over winter which means less repairs in the future. Another advantage of a trailer spray tank with a sump is you can park the trailer on the flat/hill/sloping ground (parked in a safe place) and be spraying as the chemical is sloped to the sump to drain. With these sprayers they also hold their resale value and sort after in the market as they are better quality .
