If you only have 10ft of water over the pump, you only have about 15 gal of water available to pump out. Depending on lift and pump size and recovery rate, your pump could be pumping 14gpm and easily run dry if you take a long shower or several people taking showers one behind the other. If this is the case, you need more storage, maybe a larger pressure tank, and the low pressure cutoff switch, to keep the pump from runig dry while using. Other option is to get the well company to drill the well deeper to gain more storage that way. This will be costly, but you have to have water. You also might want to look into hydrofracking the well to gain more water flow.
As already been mentioned, check wire size and use the depth of pump plus the distance from power supply to calculate the size of wire you should be using.
As for pump size, you can get by with a lot smaller pump if your stactic water level is closer to the top of the well than you can if level is really low. All you need is a pump that will overcome the static water level. I used a 1.5hp pump in a well 613 ft deep and never had a problem in over 8 years of living at that location. The static water level was 35 ft and I only had 1/4gpm of water recovery in that well. When it was drilled, we blew dust off the drill bit when it was extracted from the well. We ended up having the well hydrofracked to get more water. Hydro fracking is the process of pumping water, under very high pressure, into the well to frack/crack the rock and allow more water to flow into the well. No chemicals are used, only water. As a side note, our neighbor across the street had 2 wells and had to switch the pump out between the two every summer because one would run dry. After we fracked our well, it made the water muddy in his well, which quickly cleared up. His well never ran dry again after that, so not only did we improve our water flow, but we also helped his well.
One more comment, There is more than one kind of iron found in wells, the mineral kind, which you can do nothing about, and the bacterial kind. The bacterial kind is usually either white or red. These are the kind that usually cause the slimey sludge build up and the red or green stains in your sinks and tubs. The bacterial kind can easily be controlled using clorine bleach. Lots of people just pour a little clorox, (unscented kind), down their wells every so often to santitize their well. This methoid usually isnt really effective simply because they continue using their water and the bleach never has time to do its work. The proper way is to add the clorine to the well and then turn on every spicket in the house and leave on long enough to allow the clorinated water to flow thru each water line. At that point, turn the water off and let it set for at least 24hrs before using again. This allows the bleach enought time to kill the bacteria, in the well, and the water lines throughout the house. then you can run the water long enought to get rid of the clorine smell and the rust and sludge will disappear. It might come back, but how long it takes is dependant on how well a job you did disinfecting the well in the first place.
