How much HP do you need to pull a tube?
The motors used to power tubes need to be able to provide about one horsepower for every 40 pounds of weight. The boat should be able to reach a speed of about 20mph in order to tow a tube. If you plan on towing more than one tube, you should consider a pontoon boat with a higher horsepower. Depending on the size and engine, a pontoon boat can reach 15-30 knots (17-34 mph). Some high-performance models, designed with more powerful engines and optimized hulls, can even push closer to 40 knots (46 mph), allowing for faster travel and a more dynamic boating experience.
What psi for towable tubes?
Pumps: First, it is important to know that tubes do not require high pressure; they are low pressure / high volume products. If you could measure the pressure in a fully inflated tube, it would be around 2 PSI. Most towable tubes can be inflated using one good electric pump or a combination of 12 volt and hand pumps. Generally speaking, float tubes with air chambers inflate to 2. Psi, PVC float tubes to around 3. Psi and dropstitch float tubes, mainly used by Seven Bass for its flatforms, are inflated to 15 Psi. Some manufacturers display the inflation pressure on the valve.