Generally, they can occur from one of the following causes: 1  Infection. 2  Environmental exposure. 3  Malignancy. 4  Occupational exposure. 5  Collagen vascular disease (an inflammatory condition of the body including the lung) 6  Drugs. 7  Idiopathic (unknown causes)
01-08-2006, 09:34 AM. Check to see if you have the tap marker (handle) turned down to far. The jam nut (lever collar) for holding the marker straight should not be touching the lever bonnet. The bonnet is the nut that holds everything to the faucet. If it is touching, this will cause your sticking Faucet.
The third major cause of unexpected ammonia and nitrite spikes is old tank syndrome. This arises when tanks are not given regular partial water changes and are simply topped up instead when water evaporates. Over time nitrates build up, carbonates deplete and the water acidifies.