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garfield
20th Oct 2011, 11:50 AM
Hi All,

I let my pool go over the winter and as you can imagine it's putrid green at the moment. Anyhow I'd like to know if anyone can recommend or speak from experiences about the 4 -1 pool testing kits please?

I have problems with my pool all the time and it's a battle for me to stay on top of it and the pool shop try and sell you $500 worth of gear every time you have the water tested... so I'm thinking of buying a kit and hopefully correct what's wrong with the pool myself.

Thanks
Geoff

Ashore
20th Oct 2011, 01:09 PM
I use test strips , they measure Ph, Chlorine & Alk all in one go . Cheap quick and accurate

garfield
22nd Oct 2011, 08:31 AM
Thanks for the reply ashore.

I also have them strips, but with the 4-1 test kit I believe to also tells you how much of certain chemical you'll need to fix up the problem - where the strips just give you a reading...?

Jl350
28th Oct 2011, 02:02 AM
I probably use the test strips maybe once a month, good to check all is ok. I dose algaecide (copper sulphate active ingredient or similar) once a year, get the strongest one, it will usually be the cheapest, need to know approximate volume of pool to the right addition.

I use granulated chlorine, check the active ingredient strength, the highest is about 700g/kg chlorine, don't get sucked by the "shock" chemicals, no different to normal stuff. When adding to pool, I mix about 600 ml og granules with water to dissolve and let settle so that I can decant the solution, add more water and repeat. Add with pool filter running to circulate solution and mix chlorine in. I have about 50,000 litre pool, add chlorine about every five days in summer, and every three weeks in winter.

For pH control hydrochloric acid wil reduce the pH, and pH up will bring it up. I hardly have to adjust pH, maybe throw a little acid in every now and then, ie every couple of months.

The key to keeping the water nice is to keep the pool clean, dust, leaves etc will cause algae to grow faster, meaning more chemicals more often. I run the filter for two hours in the morning and two hours at night, after heavy use etc a couple of hours in the afternoon.

Chlorine and other chemicals affect the pH, not a lot, but enough to mess you around until you get a feel for the chemicals. If the pool is green add chlorine with filter running and clean the pool, this will take time, backwash the filter when the feed pressure gets to high, clean other leaf filters etc. Make sure pool cleaner is moving around the pool, you have to pump the pool water through the filter to remove the nasty stuff.

After six hours check chlorine levels, organic matter will consume it so if the test strip is over 5ppm you are ok, over 15ppm you probably went to far on the addition. Keep running the filter until water is clear, backwash as needed, top up water. This can take a day.

Adjust pH, take it easy, 100ml of acid can change it quickly, but you need to wait for the acid to mix, ie an hour or so, with filter running, use the strips to see what happens.

Keep pH and chlorine in the right area and keep the pool clear and maintenance is easy.

GeoffW1
31st Oct 2011, 01:39 AM
Hi,

Yes, I'd get the test kit and go with it. You don't use much test solution even testing twice a week.

One thing - the "No. 1" chlorine test tablets go off, even in the foil packet, so don't buy lots, they won't keep.

All the chemicals you need can be bought in Woolies, Bunnings, or pool shops. Many of them cannot be sent by mail order though.

Your green pool is due to algae, so you will need a lot of algaecide, and clarifier, and your filter will need cleaning more often for a while. You might also need "starver" to remove phosphates, if there is a lot of that nutrient in there for the algae.

Get your test kit and..

- remove all leaves and crap, and vacuum the bottom
- brush the walls down to dislodge algae
- adjust the pH with acid (down) or sodium carbonate (up)
- run the pool for 1/2 day and check the chlorine
- add chlorine or adjust the chlorinator as needed to get the level up high, a "shock" dose of 10 mg/L
- run the pool for 1/2 day
- when chlorine level is OK, at least above 3 mg/L, add algaecide at the recommended "shock" dose
- it is best to add the algaecide to a bucket of water first and distribute that around
- run the pool for a day or 2, check the chlorine again and clean the filter
- if the pool is still green, repeat all these steps from pH adjustment on
- add flocculant (clarifier) at the recommended rate. This causes all the dead algae to fall to the bottom. Note this often has to be added to the skimmer box. Follow the instructions on the bottle
- vacuum all the sediment. Clean the filter
- the pool water should then look much better, but you might need to run the filter for some days yet before it sparkles.
- use algaecide at a heavy maintenance rate, and repeat all the above if algae reappears, also..
- if algae is very persistent, use "starver" to remove any phosphates in the water, which are algae nutrients

Down the track, use your test kit to maintain chlorine level, pH level, and also total alkalinity level. This last requires "buffer", which is added to stop pH "bounce" or instability. Buffer is sodium bicarbonate, and it will raise pH, but not as much as "pH Up", which is sodium carbonate. Note that total alkalinity level in some pools (eg fibreglass) cannot be got up to the recommended 100 ppm, and the highest you will get is 60 ppm or so. It just means you have to check it a bit more often.

Cheers

Compleat Amateu
2nd Nov 2011, 10:50 PM
I've had many of the same battles with our pool - wouldn't own another, that's for sure. I use the 4 in 1 kit, and occasionally take the same sample to the poolshop as a confirmation that it is about right. Poolshop testing normally records slightly lower.

Others would think I'm obsessive, but I maintain a spreadsheet of test results and have, over a long time, worked out Winter and Summer settings for filter time and chlorine dispenser (my pool has a Rola that I'll chuck when I can). Long stoy about why MY pool is so susceptible to weather, pH variations, leaves, jamming dispenser, etc, etc et-bloody-c! I'm starting to rant.....

So the hardened view of an amateur poolboy would be that 4 in 1 is a useful adjunct to shop testing (or the other way around), and both should tell you approximately the same story.

And GeoffW1 above is on the money. Nuke it til it glows for a few weeks; but then keep it under control, just take more time and effort tha you'll soend swimming ... sorry, ranting again!

Good luck
Compleat