A hydration bladder is a soft, durable water reservoir that sits inside a pocket on your PFD or backpack, allowing you to drink hands-free via a tube while paddling, foiling, or sailing — without stopping or removing your vest. For athletes spending long hours on the water, a hydration bladder is essential kit. Vaikobi offers three sizes to suit different session lengths and PFD setups:

• 1.5L Bladder — for longer sessions such as downwind runs, ocean racing, and extended training. Fits in the back pocket of the V4, VXPII, VXI and VXS.
• 1L Bladder — a versatile mid-size option. Fits in the front pocket of the VXPII and the back pocket of the V-Impact Vest.
• 500ml Bladder — compact and lightweight. Fits in the front pockets of the V4.

Read our complete guide to hydration bladders or shop hydration bladders.

Yes, all Vaikobi PFDs are designed with dedicated hydration bladder pockets for hands-free drinking on the water. Here's a breakdown of which bladder fits which PFD:

• V4 — two front pockets fit the 500ml bladder, plus a large back pocket for the 1.5L bladder. The most versatile hydration setup.
• VXPII — front pocket fits the 1L bladder, large back pocket fits the 1.5L bladder.
• VXI — large back pocket fits both the 1.5L bladder and the 500ml bladder.
• VXS — large back pocket fits the 1.5L bladder.
• V-Impact Vest — large back pocket fits the 1L bladder.

All bladder pockets include hose guide tabs for easy routing to your mouth without disrupting your stroke. Shop hydration bladders.

Even mild dehydration reduces endurance, slows reaction times, and increases fatigue on the water - and by the time you feel thirsty, it's already too late. The key is drinking small amounts consistently throughout your session, hands-free via a bladder hose, without breaking your stroke or foiling rhythm.

As a guide:

• Over an hour on the water — bring a bladder. On the water you don't feel yourself sweating the way you do on land, so it's easy to underestimate fluid loss.
• Downwind runs and ocean racing — essential. Long open water sessions with no opportunity to stop make hands-free hydration a must.
• Under an hour — water before and after is usually enough.

Read our hydration on the water guide and find out which hydration bladder is right for you.

A good rule of thumb is to drink 150–300mL every 15–20 minutes during exercise. For sessions over 45–60 minutes, consider an electrolyte drink rather than plain water to replace what you lose through sweat. As a guide, the 500mL bladder suits shorter sessions, the 1L covers one to two hours, and the 1.5L is the go-to for longer distances or hot conditions. See the full hydration bladder range or read our hydration bladder guide for a full breakdown.

Cleaning your hydration bladder after every use is essential to prevent mould, bacteria, and taste issues. Vaikobi's 1.5L hydration bladder includes a cleaning kit, here's how to use it:

• Rinse the bladder with clean fresh water after every use
• For a deeper clean, use the included cleaning brush to scrub the inside of the bladder and the tube
• Leave the bladder open and fully dry before storing - never store it sealed while damp
• Store the bladder in the freezer between uses if you want to prevent bacteria growth between sessions
• Avoid using harsh detergents - a small amount of bicarbonate of soda and water is an effective and safe cleaning solution

Read more in our hydration bladder guide.