Scoop on Ideal Total Alkalinity (and Use of Pucks)

[GMusic]

What is the ideal total alkalinity for plaster/bleach? I always thought it was around 100.

80-120 seems to be what is commonly out there. The TFP ABC’s of Pool Water Chemistry says 60-120 for total alkalinity in general. The TFP Recommended Levels article in the Pool School is 70-90+ for plaster/bleach. Does 90+ mean 120?

 

[JoyfulNoise]

There is no “ideal” value. The best you can do is target a TA value that keeps your pH rise (or fall) to a minimum. For most pools, pH is always rising due to carbon dioxide outgassing. So a low TA (below 80ppm) and high pH (7.6-7.8 range) is usually good.

 

[GMusic]

Thanks. Why are the common TA ranges generally too high?

 

[AUSpool]

The range is quite broad but it is just a range, from the low end to high end. I’ve never been given a good reason why LPS and the industry in general recommend being in the high end but if they do and tell you to maintain a pH between 7.4-7.6 they sell lots of cheap bicarb packaged as expensive alkalinity increaser.

 

[Leebo]

Thanks. Why are the common TA ranges generally too high?

Additionally keep in mind the amount of users who use Trichlor (pucks) in their pools. These pucks are very acidic and generally want to push the pH of the pool down. If a user has a low TA the pH will crash very easily. The higher TA levels help prevent a dangerous pH level by making it harder to push the pH down.

 

[GMusic]

I wonder if one could use a small number of Trichlor pucks to keep the CYA at a stable level and offset the tendency of the PH to drift upwards.

 

[ajw22]

I wonder if one could use a small number of Trichlor pucks to keep the CYA at a stable level and offset the tendency of the PH to drift upwards.

The philosphy of TFP is simple pool care. Trying to balance LC with TriChlor and keeping the FC, CYA, and pH all in balance will be anything but simple.

 

[DuaeGuttae]

The philosphy of TFP is simple pool care. Trying to balance LC with TriChlor and keeping the FC, CYA, and pH all in balance will be anything but simple.

I thought the philosophy of TFP was knowing what your pool needs and using just that and nothing else. For me floating a couple of Trichlor pucks helps keep my high TA fill water from raising the alkalinity in my pool. It lets me add acid less frequently.

I’m not an expert, just a person who has learned a lot about pool care from a great team of local people and this site. I started with liquid chlorine, then moved to a SWCG, then about one year ago bought a trichlor floater and my first ever pucks. I think it was reading a post by @mknauss where he said he used them to manage pH rise while on vacation. I bought them to test how they work in my pool, and I found that use of them empowered by the chemistry education on this site has made my pool care more trouble free. The SWCG is still my source of chlorine, but using occasional pucks helps keep my CYA up and pH down.

Maybe it’s just the folks in the Southwest with high temperatures and very alkaline water who will have this experience?

 

[GMusic]

Maybe it’s just the folks in the Southwest with high temperatures and very alkaline water who will have this experience?

I think I have had the exact same experience.

I was using a few pucks just to augment the TFP system and everything had been stable for quite a long time. I stopped using the pucks a few weeks ago and my pH quickly went up and my CYA went down. So I was wondering whether the pucks might have been helping to manage these drifts.

I know it can be necessary, but I hate using muriatic acid.

How many pucks do you typically use?

 

[AndyTN]

The philosphy of TFP is simple pool care. Trying to balance LC with TriChlor and keeping the FC, CYA, and pH all in balance will be anything but simple.

I definitely disagree that bleach and trichlor can't make a simple combination for pool care. I have my feeder on the lowest setting as supplemental FC and add a gallon of 10% bleach every 3 days. My CYA in mid June was around 40 and I use about 1 puck per week. PoolMath says my CYA would have risen by 15 or so during that time period but it hasn't even been that much and it is just under 50 (round up). Maybe this is due to some very heavy rains we had in July and I do drain out 1-2 inches of water when I do a good backwashing every 2 weeks.

By every 3rd day, my FC has drifted down to about 3-4 and when I put in the gallon of bleach, it hops up to 7-8. I have had no problems all summer and I have only used a gallon of muriatic acid the entire summer with ph consistent at 7.6-7.9. My alkalinity stays very consistent at 80-90 with only adding 3 lbs of baking soda every few weeks. I don't even log stuff in PoolMath anymore because it is so consistent.

TFP method has taught me to know exactly the effects of everything I put in my pool and to get on a consistent schedule. I am told on this site that "you doing it the pool store way" when I mention that I use trichlor but my pool came with a Rainbow feeder and the FC from trichlor is technically cheaper than bleach so I'm doing what works best for my situation. Maybe my CYA will get up to 60 or so by the time I go to close it but I will drain out almost half the water to close for winter and end up with CYA around 20 come spring opening.

 

[ajw22]

You can manage your pool your way. Those techniques are not something you will find in TFP Pool School. We help educate you so you can decide what you are comfortable doing.

 

[Donldson]

My advice is to never take advice from someone with 4 whole months of experience claiming "well this isn't how TFP does it but it works for me". Because those people don't know what they don't know and what they don't know can lead to some major problems.

GW: let your TA drop and your pH will stop rising. It's that simple. No need to start throwing new things in to the mix just to make your pH stable in "ideal TA" fantasy land. Which won't work anyway since the pH rise from 100+ TA will require more acid than a puck or two a month can offer. The very first reply you got had the straight and simple answer. Trying to use trichlor to keep the pH balanced at a high TA is a solution to a problem that doesn't exist which will bring all new problems to the table. What is this, a government contract?

 

[Jeff J.]

The philosphy of TFP is simple pool care. Trying to balance LC with TriChlor and keeping the FC, CYA, and pH all in balance will be anything but simple.

I thought the TFP philosophy is:
1. Use only EPA approved sanitizers.
2. Test regularly with an accurate test kit.
3. Know the effects of different chemicals, levels, and adding various chemicals.
4. Within those guidelines, do whatever makes you happy.

Hopefully, of course, safely, cheaply, and with the least effort.

 

[GMusic]

Hopefully, of course, safely, cheaply, and with the least effort.

Add "effectively" and I think that sums up the goal of the entire pool maintenance process.

 

[AndyTN]

My advice is to never take advice from someone with 4 whole months of experience claiming "well this isn't how TFP does it but it works for me". Because those people don't know what they don't know and what they don't know can lead to some major problems.

First off, I was not giving advice but was simply recapping my experience to refute the comment that bleach and trichlor in combination won't be simple. I am not using the trichlor for any purpose other than supplemental FC and I measure CYA frequently with the known consequences of letting it get out of control. My CYA has not increased like everyone has warned and my water is very cheap to do any needed water exchanges. I am using it in moderation with a secondary benefit is that it helps keep the ph from drifting up and I am pointing out that I my pool has been very trouble free this summer using this combination. I haven't had to do the sock method with CYA granuals because I am slowly increasing CYA for free with trichlor. MA is not really cheap for frequent use and I hate using it because it is so harsh/corrosive.

I have been using the TFP website for the past 4 years to gain a lot of knowledge and just starting posting questions/replies this past Spring. I know I am a newbie but instead of stating that what I have posted recapping my experience should be disregarded, please chime in with reasons besides high CYA that my approach will have problems. Do we need a certain number of years or comments on the site to be able to share with others our experience/approach?

 

[DuaeGuttae]

I think I have had the exact same experience.

I was using a few pucks just to augment the TFP system and everything had been stable for quite a long time. I stopped using the pucks a few weeks ago and my pH quickly went up and my CYA went down. So I was wondering whether the pucks might have been helping to manage these drifts.

I know it can be necessary, but I hate using muriatic acid.

How many pucks do you typically use?

I don’t use many pucks, perhaps only a total of six pounds in the 2 years I have owned the pool. I bought a small package last August because I wanted to experiment with them while I was home to watch the chemistry so that I would have some idea of what they did to my chemistry before I attempted to use them for a winter vacation when my pool would be open but the water temperature too cold for the SWCG to operate. I was down on my CYA levels anyway after a hot summer, but what I discovered was that floating the pucks lowered my alkalinity to a spot where my pH rise was much more manageable. My fill water has an alkalinity of 290 so with evaporation and topping off, it’s hard to get my TA below 100 even with lots of muriatic acid. I will admit that I’ve never spent days purposefully lowering the TA because I’ve known it would rise anyway. (We store rainwater also for topping off the pool to help keep calcium and TA in check but since July, it’s been all hose water because we’ve had no rain, and the tanks go for the garden and landscaping.)

I did use both liquid chlorine and a few pucks over the winter. We had torrential rains last fall that overflowed my pool and required draining excess on more than one occasion. I believe it was the most rain this area of Texas has received since records have been kept. All that fresh water lowered my CH, my TA, my CYA, and my salt. I haven’t checked my records but I think at one point I actually did add baking soda so that my CSI wouldn’t get too low with the cold temperatures, and I didn’t want to use too many pucks and risk crashing the TA.

It’s been a steady diet of SWCG chlorine and MA this summer until last week when I needed a bit of a reprieve because of back-to-school season. I don’t rely on the pucks to provide my chlorine, though they have bumped it up a bit, but they had as of this morning kept my pH at 7.7 for over a week and brought my TA to 90. The TA is probably up a bit, though, because it was the day we’re allowed to top off the pool (water restrictions). So my puck use this summer has been 4 8 oz pucks that are still not completely dissolved in a floater. My CYA was below levels recommended for my SWCG when I put them in, and even these won’t get it quite high enough, but I’ll retest before considering whether I want to put another in the floater.

I’m certainly not trying to argue against TFP, and I sincerely believe that the education here has allowed me to make good decisions for my pool care. There’s another thread over in The Deep End that I read this afternoon that discusses using both liquid chlorine and trichlor and is worth a read.

 

[GMusic]

Thanks for the information.

I read the thread I think you were referring to.

I have a SWCG as well, although right now I have just been using LC. I am sure that starting up the SWCG will alter things a fair amount.