7.2 vs >8.2 Grrrrrrrrrrr

[Infidel]

Part of the problem with checking the Cl is that I have pretty wide margin of error due to dilution, I'm probably looking at +/- 20ppm when I look at the comparator and the color is between the 3 and 5, and I'm at a 5x or 10x dilution. I could have 10-15ppm of Cl consumed immediately and not be able to detect it on the test kit.

I'm using the poolcalc to determine the 12.5ppm, it's more like an 8K gallon pool, I'm using 6% bleach in 1.7 gal jugs ~12.5ppm addition/jug.

I agree that the free Cl could be consumed within a few hours, leaving me below the breakpoint/shock level for too long. I'll add more frequently. I know the consequences of not enough Cl, but I'm not sure there are any bad things that can happen if I over chlorinate. With my high CYA and organic issue I think that a high Cl condition wouldn't persist very long. Wife and kid swam today with elevated Cl with no issues, about 4 hours after the last 12.5ppm addition, there's actually not a lot of Cl odor either. It's either getting consumed breaking down organics or it's not available due to pH or CYA issues. Ph is maintaining around 7.2.

[Infidel]

A 22.5ppm jolt this am leaving for work, nice and blue by the time I got home.

[brent.roberts]

congrats !!

you've almost earned your stripes as a true beleiver in the BBB method.

keep the filtering going and hold the CL pretty high for a couple more days

Brush it everywhere to uncover any living algae that may be hiding under a layer of dead slime.

Next week you need to get a handle on the high level of CYA.
I don't recall if you were using stabilized chlorine ( pucks or tablets ) that continually add CYA, but it is a pretty common trap. The CYA keeps going up and the owner sees the CL levels at 3 to 5 and thinks everything is just dandy.
Then the frog pond hits and until you learn that CYA at 100 or more is counter-productive, nothing clears up the algae ( for very long )

The other good news about all this is that the algae ran up the red flag. If algae can grow, so can the nasty bacteria that may make you and the kids sick. Coliform can flourish in the same soup as algae and if the pool didn't go green you might had a rough time until the connection got made that the pool was the source of the infections.

Keep it up. If you need help on a few trick to get the CYA down, there are lots of good folks here to help

[Infidel]

Thanks Brent. I inherited the pool when I bought the house a year ago, it has an inline chlorinator that takes pucks, the previous owner used pucks adn the pool guy that oriented me used pucks, so, I've used pucks. I haven't used a puck yet since finding this site but the damage is done with CYA at 100+ from years of puck use. I'm considering a 50% water change, maybe at the end of the season though.

Now, did I kill the algae with the supershock addition? Was I just pissing in the wind adding 10ppm every 4-6 hours. I added around 16 gallons of bleach over a 3 day period, only improvement I saw was the last 3 gallon addition which seemed to clear it up. Perhaps patience is a bad thing, and an aggressive superchlorination one time is the answer?

Anyways, my sand filter isn't too effective at filtering algae, alive or dead. Recommendations for removing the cloudiness now? I'm thinking of letting it settle to the bottom then vac to waste, seems to have worked the best in the past. Recent rainfall has given me the extra volume I need to send it to waste.

[denanbob]

What does vac to waste mean? I've seen this several times and I'm trying to figure out what it means. Can anyone help a newbie? Thanks!

[CarlD]

What does vac to waste mean? I've seen this several times and I'm trying to figure out what it means. Can anyone help a newbie? Thanks!

Normally, when you vacuum a pool, you plug the hose into the skimmer or the low drain and the pump sucks all the junk out of the pool while you vacuum. You can either direct that dirty water through the filter and let the filter try to clean it (and if some of the dirt is too small it may not) or you can redirect the water to a drain--to waste. Some filters, like sand filters, have a valve on top that allows you to:
1) filter the water
2) simply circulate the water and bypass the filter
3) backwash the filter (force water through backwards knocking the junk loose and directing it to a drain)
4) go directly to the drain and not filter it.
5) block off the filter and pump.

There's a 6th position but I don't remember what it is.

Some filters, like cartridges, don't have a valve like this and you must either open a port on the bottom or just plan on cleaning it.

You can also vacuum to waste by syphon if you can get the hose end outside the pool lower than the pool bottom. The natural syphon acts like a vacuum and by definition vacuums to waste.

[brent.roberts]

Infidel

There really does seem to be a "break point" as some folks here call it.
With your super high CYA your break point will be way up there. Sometimes the advice given here is a bit conservative because some folks with vinyl lined pools might take the method and end up bleaching their liner. Not your problem with a concrete/plaster pool.

Vac to waste will be a good idea. Shut down for a couple hours, let it settle, set up the vac, switch to waste then start the pump and it will be most effective.

When you finish that backwash the filter, get a small bag of Diatomacious Earth (DE). Set the valve on filter and note carefully the pressure reading. Then add DE to the skimmer a cup or two at a time until you see the pressure go up 1 PSI. Keep t

he pump running like that for a couple days. The DE will help quite a bit to get the finest dead algae out. Don't inhale. Not the grass... the DE. The pool grade DE is not good in your lungs.

You should by now have seen the famous "best guess" chart for the chlorination level vs CYA levels. Take good note. You will need to keep the chlorine at pretty high levels until you get the water exchange done. Try diluting the CYA test with distilled water to see just how much above 100 you are. Keep your PH in the 7.2 - 7.3 range and the CL you do have will be more effective.

Good Work.

[Infidel]

Thanks, I lurked for a while before registering, and I usually search pretty thorougly before posting, it was the pH issue with the 2 test kits that initially had me lost.

Let the pool settle over night, not a lot settled out. I'm going to add some DE, which I've been meaning to do for a while, I've always been dissapointed in my sand filter. I need to double check my pH as well.

As for maintaining the Cl level, I'm at a loss. I can't differentiate the color very well and I've got a 5x dilution, 15-25ppm is the best resolution I can get at my levels. Is there a better test kit out there with a more definitive end point for high Cl? Is the DPD-FAS more accurate than the Taylor kit I'm using?

BTW, what can I do with the 30lbs of stabilized pellets I bought shortly before finding this site?

edit: I should add, it may seem tedious to continuously have to explain what DE is, or what vac to waste is, but there's a lot of new people not familiar with things that appreciate the information. There's nothing more annoying than a bunch of old guys on a forum that rip people's heads off for asking questions that everyone else considers common knowledge. Thanks.

[brent.roberts]

Heads don't roll on this forum. (except maybe for those of "poolstore" salespersons )

The FAS/DPD test goes like so
put an amount of pool water into a test tube
add a tiny scoop of a powered dye, it will turn the water red/pink
add a reactant a drop at a time and swirl to mix between drops
suddenly on one drop, the pink goes clear ... done
depending on the kit you use the # of drops to calculate the free chlorine, usually by dividing by 2 eg. 7 drops = 3.5 Parts Per Million ( PPM ) of free chlorine.

That's only half the story though. You need also to find you "combined chlorine" levels. Combined chlorine was at one time, free chlorine in the pool. It has partially reacted with organics in the pool ( worms, leaves, grass, insects, kids pee etc) and has partially oxodized them. This is the source of the stinky chlorine smell you will find around a lot of pools, especially commercial or public pools. It forms this intermediate step because the free chlorine levels were not quite high enough to finish the reaction. So we test for it. If we find much of it we know the job has not quite been done. The solution is, strangely enough, jack up the chlorine levels. This is called shocking. Shock is not a product, but lots of pool stores like to sell stuff that is labelled shock. Shocking is simply bringing up the free chlorine levels to finish the oxodization and eliminate combined chlorines.

So the second half of the test is to discover you Combined Chlorine (CC) level. The FAS/DPD kit has a 3 dropper bottle to do this test. Again it is a clear solution or red solution result and easy to read. If you CC is 0.5 PPM or greater, you increase your chlorine levels for a day or so ... until the CC is back below 0.5 PPM

The kit that Ben sells here has both the easy "shades of yellow/pink/red" test , (aka OTO test) that you say you have problems reading. By the way it is widely believed that women can read that color test better than men. Ben's kit is a great package. His delivery is a bit slow at times. You can also get a pool store to order an FAS/DPD kit for you.

Hope all this helps.

[brent.roberts]

About the 30 lbs of tabs. Keep them on hand. If you know the calibrations on you feeder, it will do a better job of tending the chlorine levels in you pool if you're out of town for a few days ... than most neighbours/well intended freinds. It is know a stabilized chlorine and has very long shelf life. Wrap it well and store it in a cool corner in the basement.