Staining in spas can be caused from metals and non-living organics. Metal staining can appear in color as: blue, green or black (copper), rusty brown or greenish/brown (iron). Non-living organic staining is usually brown in color.

Water discoloration may be caused by either metals or algae. Metals in the water can come out of solution, which in turn can cause water discoloration or staining.

Calcium Hardness is the measurement of calcium minerals in the water. The calcium hardness level in spas is an important part of water balance. If the Calcium Hardness level is low (soft water), it can corrode the heaters, damage the surface of the spa and contribute to foaming issues. If Calcium Hardness is too high (hard water), it can cause scale build up and cloudy water. 

Foaming is usually caused by a high organic load in the spa water. Organics are introduced to the spa by bathers from hair products, deodorants and lotions, laundry soap residue, etc. Another cause of foaming is from a high Total Dissolved Solids level. They only way to reduce your TDS level is by draining the spa. 

Odors can directly be caused from organic contamination. On average, a person contributes 16oz of organic waste in 45 minutes in a spa. Another cause of odors could be from improper water balance. 

Skin and eye irritation may be caused from the following: