My backwash is always brown. For the fas-dpd test, you add a heaping spoon, not less, but with high FC adding more than a heaping spoon may be required. You'll want the sample to be bright pink before adding drops of r0871

It has always turned a bright pink, but the more I scoop the more drops I have to put in to get it to turn clear.

It takes more powder at the higher chlorine levels. Just add enough powder to turn it hot pink every time and you'll have enough.

I can easily use less than 1 scoop when FC is lower than 10ppm.

All the powder in the world won't turn a 0ppm sample pink btw.

Well I took the water sample to the pool store yesterday. They said I did not have any iron or copper in the pool. They wanted to sell me some stuff for black algae based on the fact that the water is green. They said if that doesn't work then we can try something else. I declined that. Today the pool is starting to look better. I got in this morning and vacuumed the pool. I think it is finally starting to get better.

That's not how it works.

The more chlorine that is in your sample is what will require more drops to make it turn clear. The amount of powder is not relevant.

I believe you, as you have a lot more experience with this than I do, but I kept retesting each sample multiple times and it did seem to take more drops if I used more. I would drop, swirl, drop swirl, drop swirl, etc. Is it possible that the harder you swirl could cause a variation in the number of drops (as in maybe in some test I did not swirl it hard enough before putting in another drop)??

Thanks for all the help. Here are a few questions that I asked earlier in the thread that were not answered yet. If anyone knows the answer to these I would greatly appreciate it.

Wouldn't the CC be rising if there was bleach eating the algae? Or am I keeping that "at bay" due to the fact that I keep adding bleach?


My pool has a green tint, but the walls and bottom of the pool are not slimy at all. The green tint was there as we were filling up the pool. Isn't that odd?

Also, when I put the water in a clear plastic cup it is clear water, no green. So wouldn't that suggest the the algae is coming from the walls and bottom? But like I said, they are not slick at all.

Where did this water come from? Well water or fire hydrant water can have rust, as can water delivered by a water truck. A tiny bit of yellow or brown may be invisible in a cup or in 3 or 4' of water but noticed as you look through 10' of water diagonally.

You don't always get rising CC levels if you are fighting algae. CC is an intermediate stage of organics being broken down, it may or may not build up, depending on the rate of creation vs the rate of dispersal via wind and sun and chlorine. I liken it to having a fever, if you have a fever, you are fighting an infection of some sort almost always, but you can have an infection and not have a fever.

It is city water from the hose. No well or hydrant.

Thank you for the explanation on the CC.

On the FC test; you are to use a heaping spoon of the powder, so that some is left undissolved in the bottom of the sample. I assume that with higher FC levels, more of the powder would be needed, so that if you did not use enough you might get an incorrect value. There are "extended directions" that cover this, as I recall.

On the FAS-DPD test, if you don't use enough powder it'll affect the test. Using too much isn't a problem. If adding more powder gets you higher numbers then you should use more powder.

Thanks to everyone's help...my pool water is beautiful now. It seems I needed to scrub the walls. The walls were not slippery; so, I assumed I didn't need to brush them. I guess I was wrong. The water is clear and blue now. I just have to do the Overnight test to see if I can stop shocking. So far I haven't had a problem with CC >0.5 and the water is clear. That just leaves the OCLT test!!

Thanks Again to everyone!!! I look forward to a trouble free pool now!!!

Sounds great! Good luck on the OCLT!

Thank you...257WbyMag, Beamup, Richard320, linen, frogabog, RobbieH, dmanb2b, duraleigh, anonapersona, and Bama Rambler!!!

Well I just became a Lifetime Supporter. I moderate for a nursing website (the profession, not feeding babies) and I have to say this site is top notch. It is the moderators and the members that make this site so great. Keep up the wonderful work. I hope to be able to help others one day like I was helped.

And as you support this site, it remains free for everyone. As it should.

Welcome to the club! (not a very elite club... we hold no members only parties, but you do get the cool banner under your ID to sport forever!)

Here is a before and after for everyone...


water1 by j_b_photos, on Flickr


blue pool by j_b_photos, on Flickr

Lookin great jb2u can I come over to swim?

Well it would only be fair seeing how you helped get it this way!!!