The most commonly damaged piece of rowing equipment is the skeg, which is a metal or plastic fin that comes out of the bottom of the boat to help maintain stability, and to assist in steering. Since the skeg sticks out below the hull of the boat it is the most vulnerable to damage, however it is relatively easy to replace skegs by gluing a new one on. Hull damage is also a significant concern both for maintaining equipment, and for rower safety. Hull damage can be caused by submerged logs, poor strapping to trailers, and collisions with other boats, docks, rocks, etc.
The main advantages of the water rower are that it has quiet operation; there is only little maintenance to do, the water only needs to be changed occasionally; many users love the whooshing sound of water in the tank; and its consistently smooth resistance at every stroke. Two disadvantages of this machine are it costs a lot than the air rower; and it tends to be larger in size compared to the other rowing machines.

When waves run into water moving in the opposite direction, they are slowed, just as if they were approaching a beach. Wave length becomes shorter, wave height higher, and they may break. A good (bad) example of this is an ebb current flowing out of Raccoon Strait into waves coming in from the Golden Gate. Good rough water training, if that’s what you want.
Flywheel sits in enclosed water tank to provide smooth, quiet, self-regulated resistanceSeries 4 performance monitor tracks workou...t intensity, stroke rate, heart rate, and moreHandcrafted rowing machine with "water flywheel" that replicates actual rowing feelStores upright; measures 83 x 22 x 21 inches (L x W x H) and weighs 108 poundsNo impact and Non-Load Bearing, perfect for users with Joint concerns read more
The First Degree Fitness Challenge AR (Adjustable Resistance) is designed and engineered by professional rowers and craftsman using only the highest degree of quality components – ensuring complete satisfaction in function, performance, and reliability.  With its patented Fluid Technology, First Degree Fitness has incorporated the truest emulation of sensation, sight, and sound of real on-water rowing captured in the private setting of your own home.

This affordable rowing machine is streamlined, simple to use, built well, has a comfy seat with a realistic rowing movement, and especially good for a newbie. Because the cost of this machine is less than $150, it is popular on the net. As it has a hydraulic rower, resistance is provided by just one piston under the main key column. Along with a comfy cushioned seat, LCD screen, this machine provides 12 hydraulic cylinder resistances.
Motion of the water is different than the motion of the wave. Water at each location moves in a circular path, but the motions at different locations are “out of phase”, which means that when water at the left of the diagram is moving to the right, water a quarter of a wavelength to the right is moving down, and water next to it is moving to the left, and next to it is moving up, etc. The overall effect is a an “apparent” wave moving to the right. Thus, the velocity (speed) of a wave is not at all the same as the velocity of the water.
The rowing machine itself is unlike any other on the market with its patented water filled flywheel. It is hard to exactly copy the action of a scull on the water, but the mechanics of the flywheel spinning in water comes in a close second on dry land. The fact that the water is 800 times denser than air means that there is no need for any extra resistance or dampening that you will find in normal air rowers. The faster you pull, the more resistance is generated giving it infinite variability. However, if you want to be able to practice rowing with a faster stroke, you will have to reduce the amount of water in the tank unlike an air rower where you just have to adjust the baffle.