# How to fill and clean a water rower tank Source: https://rowandspin.co.uk/blog/water-rower-tank-filling-and-cleaning Published: 2026-10-12 Publisher: Row and Spin **In short:** Fill the tank with tap water using the pump or jug supplied, up to the level marked on the tank or in the manual. Add a purification tablet at the interval the maker gives, often every few months, and keep the rower out of direct sunlight. If the water turns green or cloudy, drain, rinse and refill following the manual. Water rowers are simple machines, but the water in the tank needs a little care. The level changes how the stroke feels, and untreated water can turn cloudy or green over time. This guide walks through filling a tank to the right level, how purification tablets work, what to do if the water changes colour and how to drain the tank before moving the rower. Steps differ between models, so check your maker's manual for exact levels and intervals. ## How the water level changes the feel Inside the tank, paddles spin through the water when you pull. More water means the paddles move more mass, so each stroke feels heavier and the water keeps its momentum longer. Less water feels lighter and quicker. Unlike a magnetic rower, there is no level dial: water level is the main way to change the feel. Most tanks have a level gauge or sticker on the side. WaterRower tanks, for example, carry a level indicator, and the manual gives a recommended range. Some water rowers, such as the Dripex RW625, list a tank capacity on the listing. Stay within the maker's marked range. Overfilling can push water past the seals and underfilling can make the paddles splash. ## How to fill the tank Most makers supply a hand siphon pump and say ordinary tap water is fine. Fill the rower where it will stay, as a full tank is much heavier. Each litre of water weighs about 1 kg, so a tank holding around 14 to 18 litres adds roughly 14 to 18 kg. 1. Put the rower in its final position on a mat, with the tank level. 2. Remove the tank bung or filler cap as shown in the manual. 3. Fill a clean bucket or jug with tap water and place it higher than the tank. 4. Use the supplied pump or siphon to transfer the water into the tank. 5. Stop at the level the manual or tank gauge recommends. 6. Add a purification tablet if the manual says to do so on first fill. 7. Refit the bung firmly and wipe up any drips. Note: Keep water away from the monitor, batteries and any power lead. If water has got into the monitor or electrics, remove the batteries or unplug, let it dry and contact the maker's support before using it again. ## Purification tablets: what they do and how often Purification tablets are mild chlorine tablets that stop algae and bacteria growing in the tank. They keep the water clear. Without them, water left sitting for months can turn green or cloudy, especially in a warm room or in sunlight. Makers give their own intervals. Many suggest one tablet roughly every six months, and some suggest more often in warm or bright rooms. Use the tablets your maker supplies or recommends and follow the interval in your manual. Do not add household bleach or cleaning products unless the manual specifically says so, as they can damage the tank or seals. Keeping the rower out of direct sunlight helps a lot. Sunlight through a clear tank encourages algae, so a spot away from a window or a tank cover makes tablets go further. - Use the maker's own tablets or the type the manual names. - Follow the interval in the manual, often every few months. - Add a tablet sooner if the water starts to look dull. - Keep the tank out of direct sun. ## Green or cloudy water: what to do A slight haze can sometimes be cleared by adding a tablet and rowing for a few minutes to mix it. If the water is clearly green, smells or has bits floating in it, draining and refilling is usually the best fix. Siphon the water out into a bucket, rinse the tank with clean tap water and drain again. Refill to the marked level and add a fresh tablet. Avoid scrubbing inside the tank with abrasive tools, which can scratch it. If marks remain, check the maker's support pages for their cleaning advice. Small bubbles in fresh tap water are normal and usually clear after a few sessions. If you see water outside the tank, check the bung and the seals. A slow leak should go to the maker's support, as tank seals are model-specific. ## Draining before a move Most makers advise draining the tank before moving a water rower any distance or storing it somewhere that could freeze. A full tank adds a lot of weight and water can slosh against the seals when the rower is tipped. Freezing water can crack a tank. Use the siphon pump in reverse to empty the tank into a bucket, or follow the drain method in the manual. Leave the bung out for a while so the inside can dry, then refit it. When you set up again, refill to the same level as before so the feel stays the same. For advice on water rowers in general, see our [best water rowing machine](https://rowandspin.co.uk/best/best-water-rowing-machine) guide and [WaterRower models compared](https://rowandspin.co.uk/best/waterrower-models-compared). 1. Place a bucket below the tank height. 2. Insert the pump tube and siphon the water out. 3. Tip the rower slightly as the manual allows to drain the last of it. 4. Leave the bung out briefly to dry, then refit it. 5. Move or store the rower with a second person if it is heavy. Note: Even empty, many water rowers are heavy and long. Lift with two people where the manual suggests, and keep fingers clear of hinges on folding models. [See water rower picks](https://rowandspin.co.uk/best/best-water-rowing-machine) ## Frequently asked questions **How much water goes in a water rower?** It depends on the model. Most tanks have a level gauge and the manual gives a recommended range. Many tanks hold somewhere around 14 to 18 litres when full, but follow your maker's mark. **How often should I add purification tablets?** Follow your manual. Many makers suggest about one tablet every six months, and more often in warm rooms or sunlight. **Can I use tap water in a water rower?** Most makers say ordinary tap water is fine. Check your manual, as a few recommend a particular type of water or tablet. **Why is my water rower tank cloudy?** Usually algae or bacteria from water left too long without a tablet, or sunlight on the tank. Add a tablet for a light haze, or drain, rinse and refill if it is green or smells. ## Buying guides on this topic - https://rowandspin.co.uk/best/best-water-rowing-machine - https://rowandspin.co.uk/best/waterrower-models-compared - https://rowandspin.co.uk/best/best-rowing-machine-uk ## Sources - [WaterRower UK](https://www.waterrower.co.uk/)