Intex Metal Frame Pool Set 12' x 30" 9137806 All Intex frame pools presented in the review could boast of Hydro Aeration technology but for the first Intex 12ft x 30in metal frame pool. This basic model doesn’t provide us with such convenience. Intex 16.5ft x 48in basin features the same prism frame. However, this model consists of separate U-shaped supports connected with horizontal tubes. Thus, the construction and the size of the pool results in a more complicated assembly. Many pools are incorporated in a redwood or simulated wood surround, and are termed "portable" as they may be placed on a patio rather than sunken into a permanent location. Some portable spas are shallow and narrow enough to fit sideways through a standard door and be used inside a room. Low power electric immersion heaters are common with home spas. Many public swimming pools are rectangles 25 m or 50 m long, but they can be any size and shape. The cover is attached to the pool typically using a stretch cord, similar to a bungee cord, and hooks fitted into the pool surround. The skimmer is closed off or a floating device is placed into it to prevent it from completely freezing and cracking. Floating objects such as life rings or basketballs can be placed in the pool to avoid its freezing under the cover. Sand or DE filters must be backwashed, with the main drain plug removed and all water drained out. There are also elaborate pools with artificial waterfalls, fountains, splash pads, wave machines, varying depths of water, bridges, and island bars. Many upscale hotels and holiday resorts have a swimming pool for use by their guests. If a pool is in a separate building, the building may be called a natatorium. The building may sometimes also have facilities for related activities, such as a diving tank. Larger pools sometimes have a diving board affixed at one edge above the water. Inexpensive temporary polyvinyl chloride pools can be bought in supermarkets and taken down after summer. Shocking your pool kills off bacteria and algae that might otherwise be setting up shop. Use this chemical to lower just the pH level in your pool water. Keep in mind that adding an alkalinity increaser will also raise your water’s pH, so be sure to monitor all levels carefully. I have Intex inflatable model just for occasional uses. The manufacturer strictly recommends using only original liners and frames to make sure they fit each other and provide you with a safe, solid, and comfortable pool. The liner that comes with your pool frame is the best match. As a rule, the pit is required for frost-resistant and almost stationary models.