Taylor K 2006 TA test turns red instead of green

muss08

In The Industry
Mar 22, 2008
56
Maryland
#1
My company has a new client so I did a full chem test with the Taylor K 2006. I add 2 drops R007, swirl, then 5 R008- instead of turning green it turns red! What does this mean? No TA? If anyone can help I'd appreciate it.
 
G

Guest

#2
muss08 said:
My company has a new client so I did a full chem test with the Taylor K 2006. I add 2 drops R007, swirl, then 5 R008- instead of turning green it turns red! What does this mean? No TA? If anyone can help I'd appreciate it.
Essentially yes. What it means is the pH is low and there are no bicarbonates in the water. They have all been 'converted' into carbonic acid. Since the measurable part of the bicarboanate buffer system is the bicarbonates and carbonates this means the TA is 0 ppm. Check the pH. You will find it very low.
Best thing to do for both low ph and low TA is soda ash, which will raise both quickly. Use the base demand test in the K-2006 to determine how much to add, let it circulate for about 48 hours, then check TA (might be a bit high at this point) and make final adjustments to TA and pH.
 

waste

TFP Expert
LifeTime Supporter
Mar 29, 2007
4,160
Coastalish 'down easter'
#3
I recall a post by chem_geek saying that the reagent changed when the pH was below either 4.5 or 3.5 (my memory isn't that good) so that you'd get an instant red instead of green - I've tried to find it on PF, but my search is too general and I get hundreds of hits. Richard, if you see this, can you please reiterate the info? :bowdown: :)

If my memory is correct - the pool is an acid bath and LOTS of pH up is required (Evan, on the pools I've seen that this happens - I've added 40+ drops to get a reading on the pH and others, I've just stopped after 60 drops with no change :shock: ) All these pools had tab feeders and the homeowner NEVER tested the water (but DID buy a new heat exchanger :lol: ) [just had one this week where the new heat exchanger, cupro-nickel, has rotted out within 2 months :grrrr: :hammer: - we told him it was the pH and he still didn't fix it after spending ~$1500 for a new exchanger :evil: ]
 

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
12,082
San Rafael, CA USA
#4
If the TA test turns immediately red, then that means that the pH is 4.5 or below. Not good. Immediate addition of pH Up / Soda Ash / Arm & Hammer Washing Soda / Sodium Carbonate is required.

For example, if I take 10,000 gallons of normal pool water to start with and I simply add 27 3" (8-ounce) Trichlor pucks/tabs to it and use up the chlorine that is produced (around 148 ppm FC or just a couple of months of typical chlorine usage), then I end up with a pH of 4.06 and a TA of -4.1 which would immediately show red on the TA test. I assumed this low pH would drive out most of the carbon dioxide from the pool. This amount of Trichlor also adds about 90 ppm CYA to the pool so in addition to pH adjustment, a partial drain/refill will likely be desireable as well.

To restore the pH to 7.5 when the TA test immediately shows red, it takes about 128 ounces weight (about 14 cups) of pH Up per 10,000 gallons and much of the TA will be restored as well (assuming most of the carbonates were lost to outgassing). It could take more, depending on how low the pH really is and to be safe one can add less and remeasure. After the pH is balanced, it may be necessary to add some Alkalinity Up / Baking Soda to increase the TA, but that's easy to determine by retesting.

Richard
 
G

Guest

#8
waste said:
Evan, on the pools I've seen that this happens - I've added 40+ drops to get a reading on the pH and others, I've just stopped after 60 drops with no change :shock: ) All these pools had tab feeders and the homeowner NEVER tested the water
My experience has been the same. I never go past 20 drops and add the max amount and have them retest after about an hour and repeat to get the pH above 7.0 only because I have seen too many people overdose on the soda ash and end up with TA through the roof!