TPFC, Algae, and other settings (long post warning!)

slepax

0
In The Industry
Jan 30, 2014
40
Perth, Australia
Pool Size
28000
Surface
Fiberglass
Chlorine
Salt Water Generator
Hello all,

I wasn't too sure if this post belong in the algae section, but being that I'm also just getting started I thought maybe this is a better place. Apologies in advance for the long post!

We have had our pool installed for about six months now, since the install we've had some ups and downs with TPFC. I would really appreciate some feedback from you guys, I've spent only a few hours reading on this website and I absolutely love it!
(I went through Pool School, SLAM, and SWG)

Some additional info:
For starters I'm in Australia. Our climate is mostly hot and dry. Does my location make a difference for any of the levels mentioned on this website? For example my test kit recommends TA level of 120-150ppm for fiberglass pools, while this website recommends 60-80ppm?

So we have a medium sized fiberglass pool with total capacity 27,700 liters. The equipment is all brand new, and consists of the following components:
- Sand filter
- Variable speed pump (three speeds)
- Salt chlorinator
- Ph controller, self measuring and automatic dozing of acid

So far I have been running the pump on low speed for 7 hours a day (7-11am + 7-10pm), this should recycle the pool water 1.8 times/day according to my calculations. However because of recurring algae problems I have recently started running the pump on medium, this cycles 3.2 times the pool capacity which is way too much and we still get algae. So something is definitely wrong!

Some additional info on the settings of our pool with some questions:
- Ph is set to 7.6, and is normally maintained at that level by the Ph controller.
- Skimmer sock installed, hardly any debris that reach the pump basket.
- For that reason – no real need to backwash quite so often. Especially since the pump is running on low speed. Is that ok?
- Pump runs for 7 hours a day on low speed. As mentioned before this almost cycles twice the pool capacity, is that the only criteria? I've been told the low speed may not recycle all the water properly and a higher speed for say 1 hour/day is still required?
- We don't get a lot of debris and so I only vacuum the pool once a week (manually), by then there's some leaf and sand on the bottom but really nothing too major. Is once a week enough?
- We cover the pool with a blanket at night and take it during the day, mainly to prevent evaporation. For that reason I only need to top up with water once a week. Is that enough?
- Can it hurt having too much salt? The chlorinator does have a "low salt" indication but I assume no "high salt" indication. I'm just wondering if high salt levels can disturb the chlorinator? Would higher salt help minimising algae in any way? (my logic says that there's hardly any algae in the sea!)

I have received a test kit as part of the pool package, it's a 6-in-1 kit (by Magnor if that helps):
- My test kit doesn't include CYA, how do I test that?
- An earlier test from today showed FC between 1.0-1.5, how do I measure CC?
- Also the test kit showed TA is 90-100 ppm

Onc last question is about digital test kits, would you recommend them? Something like the ColorQ, how accurate is it?

I know it's been a very long post and I do appreciate your patience so far!!!

Thanks!
 
Last edited:
Welcome to tfp, slepax :wave:

Putting it here is fine (there would have been fine too).

For starters I'm in Australia. Our climate is mostly hot and dry. Does my location make a difference for any of the levels mentioned on this website? For example my test kit recommends TA level of 120-150ppm for fiberglass pools, while this website recommends 60-80ppm?
With a swg (saltwater chlorine generator) your pool will likely tend to go up in ph fairly quickly if you leave the TA at that high of a level (that recommendation is very high, higher than typical of the industry in general). Regardless of climate (or pool surface) running TA in the 60-80 ppm range will reduce the ph rise and also reduce the likelihood of scaling in the cell.

So far I have been running the pump on low speed for 7 hours a day (7-11am + 7-10pm), this should recycle the pool water 1.8 times/day according to my calculations. However because of recurring algae problems I have recently started running the pump on medium, this cycles 3.2 times the pool capacity which is way too much and we still get algae. So something is definitely wrong!
Normally, when no algae is present running the pump (at the low speed) just long enough to get the appropriate amount of FC into the pool from the swg is all that is required. See: http://www.troublefreepool.com/content/152-determine-pump-run-time In your case, since you have algae now, I would turn off the swg and use bleach/liquid chlorine to do the SLAM process

-Skimmer sock installed, hardly any debris that reach the pump basket.
- For that reason – no real need to backwash quite so often. Especially since the pump is running on low speed. Is that ok?
Just make sure you backwash when the pressure goes up 25% from the clean filter pressure (when pump is running at medium or high speed...probably high unless that is too much flow for your setup).


- Pump runs for 7 hours a day on low speed. As mentioned before this almost cycles twice the pool capacity, is that the only criteria? I've been told the low speed may not recycle all the water properly and a higher speed for say 1 hour/day is still required?
See the link I posted above.
- We don't get a lot of debris and so I only vacuum the pool once a week (manually), by then there's some leaf and sand on the bottom but really nothing too major. Is once a week enough?
Unless you get a lot of debris, vacuum regularly enough so you are happy with it. It takes quite a bit of stuff before you would see a noticable increase in the need for chlorine.

- We cover the pool with a blanket at night and take it during the day, mainly to prevent evaporation. For that reason I only need to top up with water once a week. Is that enough?
As long as you have the water level high enough in the skimmer so it does not vortex and start sucking in air you should be fine.


- Can it hurt having too much salt? The chlorinator does have a "low salt" indication but I assume no "high salt" indication. I'm just wondering if high salt levels can disturb the chlorinator? Would higher salt help minimising algae in any way? (my logic says that there's hardly any algae in the sea!)
Follow you swg recommendations (or slightly higher 200-400 ppm as poolschool suggests), most are not made to run very high in salt levels since this can cause a high current situation due to the saltwater conductivity.

I have received a test kit as part of the pool package, it's a 6-in-1 kit (by Magnor if that helps):
See this poolschool article on test kits: http://www.troublefreepool.com/content/124-pool-test-kits-comparisonIt can be harder to find these kits down under, but search the forum and you will find others who have figured out how to get one.

- My test kit doesn't include CYA, how do I test that?
See link to test kits above.
- An earlier test from today showed FC between 1.0-1.5, how do I measure CC?
Unfortunately, the kit your have only measures FC up to 5 ppm, the FAS-DPD kit in the link is what you need. You kit will also measure TC (total chlorine). CC=TC-FC

Onc last question is about digital test kits, would you recommend them? Something like the ColorQ, how accurate is it?
We don't. The drop based kits are more reliable and less finicky then the digital testers.

What is your CH of the pool and your fill water?

What is the TA and ph of your fill water?
 
Thanks for the prompt reply linen!

Just make sure you backwash when the pressure goes up 25% from the clean filter pressure (when pump is running at medium or high speed...probably high unless that is too much flow for your setup)

So even if low speed is showing almost no pressure I should backwash if high speed is up 25%? Before the algae I used low speed 99% of the time and high/med speed just to vacuum. I didn't see a need to backwash quite so often.

Unfortunately, the kit your have only measures FC up to 5 ppm, the FAS-DPD kit in the link is what you need

I just checked online and the FAS-DPD kit costs roughly $300 USD (AU$350) on eBay. Is that really the price for this kit???

What is your CH of the pool and your fill water?

What is the TA and ph of your fill water?

I haven't tested TA and Ph of fill water, I will do that tomorrow as it's past midnight here and something tells me the neighbours will not be very appreciative of the noise .. :D

I will also take a sample of the water and will go to the pool shop tomorrow to test, this is the only option I have now to get the full set of test results. Unfortunately, from checking online it seems no one around me sells a kit that can do more. I will ask at the shop if they have a better kit maybe.

Many thanks again, I will write tomorrow (or later today for me) once I have more information.
 
just checked online and the FAS-DPD kit costs roughly $300 USD (AU$350) on eBay. Is that really the price for this kit???

You can surely find it cheaper than that. Well less than $100 in the US. Shipping is clearly a killer for you though.

- - - Updated - - -

For more information, check out http://www.troublefreepool.com/threads/68346-Taylor-or-tf100-test-kit-availability-in-Australia?highlight=kits+australia

Maybe some of you can share an order to save shipping????

- - - Updated - - -

Or get with this member to see what you can work out http://www.troublefreepool.com/threads/70062-FS-Australia-Taylor-Reagents-(FAS-DPD-Ph-CYA-NaCl)

You'll probably still need at least a CYA viewing tube.
 
Got some test results from the pool shop today. I've scanned the report, see below.

If I'm reading this right the main issue is that FC is too low. CC is 0.5 which is ok. Is CYA the same as stabilizer? So it's also seem to be ok by pool shop standard, but not TPFC standards?

I also had a discussion with the lady at the shop and she claimed that because of our hot weather (we're averaging 34C deg over the week) the chlorinator cannot do it's job properly, and I will have to shock the pool at least once a week. Does this make sense?

I think if that's the case so why can't I just run the pump for longer? Although I'm already running it for 7 hours a day which goes against the recommendations on this web site.

So for the time being, should I just follow the SLAM process as recommended on this website?

Many thanks!

2014-01-31 Pool Test Results.jpg
 
We put little faith in pool store testing add it has usually proved to be wildly inaccurate and inconsistent ... especially for the CYA test (yes that is stabilizer).

If you maintain adequate FC, there is no reason to have to shock ... gets pretty hot here in Arizona and my SWG keeps up no problem.

Not sure where you saw that running for 7 hours go against what we teach? You have to run the pump and SWG long enough to maintain adequate FC.
 
I agree with jbliz, nowhere do we recommend a shorter time then is needed by the swg for chlorinating a pool. With that said, it looks like your swg is undersized for your pool. It is listed as a 30000L swg and that is about the size of your pool. Many swg manufacturers spec there pool size assuming 24 hour operation, which is why we recommend sizing the swg at least 1.5-3 times the pool size. In addition, if the pool store is right on your cya (I would not assume this) you chlorine is not "protected" well from the sun and it may be that you are burning up a lot of the chlorine produced by the swg during the day due to that (how much shade does your pool get).

I hope you can find a way to get a cya test kit, but if we were to believe the pool store you need to add some. Before doing that though, follow thru with your plan to do the SLAM process until it is finished (passes all three criteria...they are in my signature). Use bleach/liquid chlorine since your swg won't be able to provide the amount you need (and it will use up hours on the cell). Ignore the chemicals the pool store wants to sell you. In the meantime, inspect your swg cell and see if it has buildup on the plates. If it doesn't, then there is no need to clean it.
 
Thanks guys.

Got my pool water tested again this morning at a different store. This test was fully computerised and I trust it more as the ph level is fairly close to my dozing machine reading, and also the results make much more sense. This time it showed CYA to be very low (10ppm) and FC to be roughly the same as the other store reading. From talking to the lady in the store it seems we have not supplemented our CYA enough (last time was a few months back) and although I believed I am not topping up a lot, it was enough to drop CYA levels and from there impact FC.

I am starting to understand things much better now, mostly thanks to you guys!

Not sure where you saw that running for 7 hours go against what we teach? You have to run the pump and SWG long enough to maintain adequate FC.

I think I have confused pump run time and SWG run time. Again, things are starting to make more sense now and I now understand the two are unrelated. Pump run time should derive from SWG run time requirements, it's not just about turning the water, I wasn't aware of that before.

I can get a separate CYA testing kit at home + check at the store once a fortnight. I will do that until I can find a more comprehensive kit.

Thanks heaps to everyone!
 
Again, I think we trust the computerized store tests even LESS than the drop based store testing. There is no way to know if their computer has been kept calibrated as required and thus no way to know if the results are correct. Until you can test for yourself, you are kind of flying blind.

Try taking water to those 2 stores again tomorrow and you will likely get completely different results.
 
There is no way to know if their computer has been kept calibrated as required and thus no way to know if the results are correct. Until you can test for yourself, you are kind of flying blind.

But that'a an endless loop. How can I ever know if the CYA test kit I purchased from the shop has been stored properly??? It could have been outside, in the heat, and the chemical elements are somewhat off by the time it gets to me. I am a techie by nature, so I always prefer computerised methods :suspect:
 

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You might try having the store test for CYA again and see if they are consistent if you are having a hard time getting your own test. What you need to do is to start the SLAM soon so the algae does not continue to grow. After the SLAM process, follow our guidelines on FC and CYA and you should not have algae problems even with your temps.

The salt level is high but I'm not sure if the unit has a high salt limit. They recommend 4000 for the salt level and if I read yours right it is at 7200. If the SWG is happily making chlorine with that salt level, I would leave it alone for the time being. In the future you will want to lower the salt level to the 4000 range. Does the SWG give a reading on the salt level? If so go by that reading for now.

Computerized testing in pool stores is just about worthless. They tend to be very inconsistent and you should always trust yourself before anyone from a pool store that is trying to sell you chemicals.
 
Unless you have not added any, it is unlikely that your cya is at 10 ppm, just as unlikely that the "Computerized tester" can actually test down to 10 ppm. I would definitely trust the cya test kit you purchased over those results, assuming it is not a test strip. Post what you get.

Do you know how much cya have you added to the pool?
 
Do you know how much cya have you added to the pool?

I don't remember exactly how much cya was added last time, but it can't be more than 500g and that was roughly 10-12 weeks ago... since then I've been topping up the pool about 8cm every week (pool size is 7.7x3.5m).

I can actually check the time and quantities with the store because they should our tests history stored in their computer.
 
what percentage is your chlorinator set at
i have just been having problems as well, i'm in melbourne
i have increased pump run time to 10 hours and chlorinator to 99%
(i have a little too much salt so my chlorinator indicates high salt if i go to 100%)
(and a little piece of info i just picked up, most people cannot taste salt pools up to 3500ppm, so that will be my new target)
your chlorinator puts out 18 grams of chlorine per hour at 100%
figure on about 5ppm free chlorine loss per day
so you will need about 140 grams of chlorine just to maintain current level
you will need about 8 hours run time at 100% just to maintain current level
you really need to get free chlorine to at least 4 or 5
so either add some liquid chlorine, 2.5 litres of 6%
or run chlorinator for longer until chlorine level rises
 
Thanks aussieta.

I lost my previous reply so hopefully this is not going to be a duplicate.

Anyhow ..

I used to have the chlorinator on 75% (6/8) and then increased to 88% (7/8) after I noticed some algae forming. It didn't help obviously. There were times were it was running at 100%, but I wanted to test lower levels.

I once saw low salt on the chlorinator display, I'm not sure if it has any issues with high salt will have to check on Monday with the distributor.

Where did you find that my chlorinator makes 18g per hours at 100%?

How did you calculate chlorine requirements for my pool (140g)?

Based on this page I need 90g (I assume per day), but I also assume that this is with adequate levels of cya.

After I get rid of the algae I will increase my chlorinator/pump runtime to 10 hours as well.
 
this is the specs on your chlorinator,
http://www.willowspoolshop.com.au/pdf/Viron-ph-chlorinator-brochure.pdf

an estimate of 5ppm chlorine loss per day in summer
you can change this as you become familiar with your pool and it will change with seasons and pool use

using pool calculator
http://www.poolcalculator.com/
change top right to metric
and entering your pool size top left 27700
free chlorine now 1, target 6
top middle click calculate
change "by volume of" to chlorine gas
gives 138 grams
the line above chlorine gas gives 2244ml of 6% bleach, which is basically liquid chlorine
change the percentage to whatever you buy and it will give you the amount to add

then some dazzling maths
138 divide 18 (assuming 100%) equals 7.66 which i rounded up to 8 hours
 
5 ppm FC loss per day is higher than normal and means that at least one of the following is true: 1) you had algae growth and algae consumes chlorine or 2) your Cyanuric Acid (CYA) level is too low and you have substantial loss of chlorine from the UV in sunlight. Since algae was seen, #1 is likely to be true. You need to SLAM your pool to kill off the algae. Then, after the algae is gone and you pass the overnight chlorine loss test then, if necessary, get your CYA up higher to reduce the amount of loss from sunlight. You should be able to get closer to 2-3 pm FC per day chlorine usage unless your pool is used a lot with multiple people in it every day or with other sources of high load such as kids urinating or pets (dogs) using the pool.

As for getting the Taylor K-2006 test kit, you can get it from poolvacparts for $60 plus around $40 shipping to Australia. While not cheap, it's a lot less expensive then some direct sources in Australia. Because the shipping is high, you might get the "C" version of the kit which has more reagents and I believe the shipping is $50 in that case. saltwaterPoolParts also sells the same kit for the same price and apparently also ship to Australia.
 
You MUST get a good test kit - only thing that can be done.
Got mine in the US from PST pool supplies - good enough price & pretty quick delivery (<1 week)
You HAVE to get a LARGE kit for the FC tests though, as you're doing the SLAM & will have to do a LOT of tests.

I've got a 50,000L and run it for about 10hrs at the mo, FC is hanging on 7 steadily & it only gets about 1/2 the sun most pools do (its between the houses & gets a lot of shade before/after midday) - oh yeah, i'm in Sydney

You're gonna have to get about 2-3 15L containers of chlorine - you'll go through a LOT.
I'd say the chlorine is being consumed by invisible algae, I was amazed at how much came out with scrubbing & brushing.

I'm not 100% sure - but backwashing cleans the filter, which will reduce the organics & hopefully consume less chlorine (... my assumption there)

test kit, test kit test kit :)
 
Thanks everyone .. so I guess I really need to go and get me a good test kit .. :rolleyes:

Searching the net a bit and just wondering what is the shelf life of these kits? If I order two Taylor K-2006C kits, can I store one of them for a year or two?

It seems poolvacparts offer a decent price on shipping ($55 international express), and shipping cost is the same whether I order one or two kits.
 

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