So you have bought your home water filtration system. If it is a cheap Culligan system, you probably installed it yourself. If it was an expensive high end home water filter, the company probably sent a technician to your home to install the system. Are your troubles over? I'm afraid not ... you have just exchanged one set of troubles for another.

1. Many people who install home water filtration discover that their water flow slows down a lot. Maybe three, four or five times slower than before they installed the water filter. The higher-end the filter, the slower the water. For example, a reverse osmosis water filter is only 5% to 15% efficient. This will slow down your water flow a great deal. A good reverse osmosis filter actually has at least two more filters - a sediment filter to remove coarse sediment and a carbon filter to remove chlorine, fine sediment and organic chemicals. These extra stages of filtering further slow down what is an already slow system. If you do not have high water pressure, this could be a big problem.

2. Some people find that their home water filtration system works fine at first, but after a few weeks their water flow slows to a trickle. This is especially common when there is a lot of sedimentation in their water supply. This sediment quickly chokes up their water filter. The better their water filter, the faster it chokes up. And then the replacement of the water filter cartridge bursts their budget. Ironically, they may have been better served buying a lower grade water filter, for example a 50 micron filter instead of a 0.5 micron filter. Or spent a bit more on a two stage water filter, where there is a cheap sediment filter to remove sediment and an expensive carbon filter to remove chlorine and organic chemicals.

3. Some people discover that they do not know how to replace the water filter cartridge on their home water filtration system. It seemed simple enough when the salesman showed them. But it has been six months since the demonstration, and now that they need to replace the cartridge it no longer seems so simple. For example, take this excerpt of instructions for the Aquasana water filter.

There are two replacement O-rings, and they need to be flat to make a good seal. Lay them out and let them flatten on their own. You may need to place a book on top of them overnight.

In most cases, your salesman probably never told you about flattening the seals and how important that is to the proper functioning of your home water filtration. Even if he did, you will probably have forgotten about it six months later.

There are two filter caps A and B ... Turn filter cap A to the right ... Turn filter cap B to the left ... Just follow the arrows ... Make sure they are only hand tight ... Be careful not to damage the water inlet and outlet.

So the filter caps turn in two different directions. At least there are arrow signs to follow, right? But will those arrows still be there after one year? Will YOUR water filter model have convenient arrows for you to follow? And why is there a warning about not damaging the water inlet and outlet? Why does the task of replacing the water filter cartridge risk damaging these important parts of the filter?

Water filter cartridge A ... is held in place by a seal on the top of the filter housing ... Use a pair of pliers ... Keep track of which is filter A and which is filter B ... Lubricate the O-rings with food grade silicone lubricant to help them seal more easily ... Do not install the O-rings dry as they may kink and cause leakage ...

And here you are told that you need a pair of pliers handy. Which is fine if you are a handyman ... but a problem if you are a nerdy librarian living alone or an elderly lady. Furthermore, what is this issue of keeping track of filter A and filter B? Shouldn't they be labeled? From the instructions, apparently not. Maybe your particular model of water filter will be fine, or maybe not. And not too many salesmen will demonstrate using the lubricant since it is too messy. Some of them may tell you about it, but will you remember after six months when it is time to replace the water filter cartridge?

In theory, you could just follow along the instruction manual ... IF you haven't thrown it away ... IF you can find it ... and IF it was written intelligibly. There are a lot of big IFs here, aren't there? Replacing the cartridge on your home water filtration unit is an important task. If the demo seems complicated, or the salesman seems to gloss over any particular step, it is probably advisable to find a different model of water filter to buy.

4. Some people find it difficult to replace the water filter cartridge on their home water filtration system. One example is the Everpure H-300 water filter. It works very well, and is not too expensive. But many people install it under their sink in a location that is out of their way. But in trying to maximize their space usage, they find that they have to contort into painful and unnatural positions in order to dismantle the filter housing and replace the water filter cartridge. In some cases, that location receives very little light and they even need someone to help them hold up a torchlight so they can see what they are doing.

The lesson here is simple - when installing your home water filter, make sure you put it in a place where you can easily get to it. Placing it on your kitchen counter may take up valuable space, but at least you can easily replace the cartridge without having to play contortionist.

5. Some home water filtration units just don't get the job done. Sometimes the model of water filter you chose is just junk - maybe you were taken in by a glib-talking salesman. Maybe the model is usually good, but you just got a lemon this time. But more likely you picked the wrong model of filter for your real needs. For example, do not complain of your water still smelling of chlorine if you bought a high quality ceramic water filter which is designed to remove ultra-fine sediment and bacteria. Don't complain if you get sick because your 50 micron carbon filter did not remove bacteria - that is not its job. Don't complain if you got lead poisoning because you bought a water filter with a resin ion exchange unit that does not target lead. And so on and so forth.

These are five of the biggest and most common problems people discover after buying and installing their home water filtration systems. To prevent these problems, think carefully about what you really need from your water filter. Do not be one of those people who write negative reviews about a product only to be shown that they were fools for misusing that product.