My deep cycle battery was not acting like it should so I checked the water level. It is too low to see under the caps. Two of my friends were there when we checked it and we had a difference of opinion. One said to use tap water and the other said to go to the auto parts store and get electrolite(sp). I thought you were supposed to use distilled water(which is what I have always used). Who is right and how high do I fill the battery cells?<br /><br />thanks<br />longshot