Pool & Spa Water Troubleshooting

problem	possible cause	check / remedy
algae growth	sunlight dissipating disinfectant	ensure disinfectant level is adequate throughout pool use algaecide
algae growth	high cyanuric acid level	dilute to reduce cyanuric acid level
alkalinity high		lower with acid
alkalinity low		raise with bicarbonate
brown staining and or brown water	iron in water (corrosion in plant)	check for water balance, adjust as necessary, use flocculant to remove, use sequestrant to prevent deposition
calcium hardness too high	accumulation of hardness salts	dilute the pool
calcium hardness too low	soft water supply	raise to 200 mgl and maintain with calcium chloride
chlorine level difficult to maintain	bather pollution	reduce bathing load
chlorine level difficult to maintain	filter blocked, turnover reduced, circulation poor	check filter, strainer, flow rate and valves
chlorine too high bleaching of dpd tablet	overchlorination	reduce by adding dechlorinator (sodium thiosulphate) or dilute the pool by draining or partially draining and refilling
chlorine too high bleaching of dpd tablet	dosing system fault	check filter, strainer. flow rate and valves
chlorine too low	under chlorination	check operatio, output and sizing of chlorine feeder
chlorine too low	direct sunlight	use algaecide if algae problem
cloudy water	heavy bathing load	introduce fresh water
	inadequate disinfection	check disinfection and combined chlorine levels, check free chlorine levels
	cyanuric acid too high	dilute to reduce combined chlorine and/or cyanuric acid
	filter/s problem, air in filter	check filters and backwash if necessary use floculant
filter blocked (pressure accross it too high	infrequent backwashing / cleaning - or scale	check and improve backwash effectivenesL consider replacing sand or use a sand cleaner
filter blocked (pressure accross it too high	incorrect coagulant dosing	check coagulant dosing: inspect filter
green staining	copper in water precipitating	test for copper, check water balance and adjust as necessary use floculant to remove and sequestrant to prevent deposition
green water	algae	check disinfection level, use algaecide, check water balance
	copper	test for copper, use flocant and / or sequestrant
	high cyanuric acid	check cyanuric acid level and dilute if necessary
ph difficulty to change	water to buffered - alkalinity too high	check and lower alkalinity
ph too low	acidic product being used acid detergent being used around pool	add sodium carbonate
ph too high	alkaline product being used alkaline detergent being used around pool	add acid to reduce
ph is unstable	alkalinity too low	raise alkalinity to acceptable range
ph is unstable	dosing eratic	check dosing accuracy and frequency
salty water	t.d.s. too high	reduce by dillution with fresh water
scale formation	water ot of balance	check water balance and adjust
test kit readings for chlorine residual unobtainable	chlorine levels too high	test a 50:50 diluted water sample
test kit readings for chlorine residual unobtainable	chlorine levels too low	check chlorine dosing
water clarity generally poor	wrong filter or incorrect use	check filtration type and rate, sand condition, procedures (backwashing etc.)
	insufficient chlorine	check and correct free chlorine residual
	no coagulant	chech coagulant use
water has bad taste or smell irritates eyes and throat	high combined chlorine	test for copper, check water balance and adjust as necessary use floculant to remove and sequestrant to prevent deposition
water has bad taste or smell irritates eyes and throat	ph incorrect	check and correct if necessary