I think it is algae now....

[waterbear]

You have, once again, missed the point entirely. Using monochloramne to kill algae is very different than killing algae with chlorine and it is also very different than using either chlorine or chloramines for sanitation of drinking water so the studies you cite are not meaningful to the discussion. You are comparing apples and oranges. These are exactly the same type of studies that are often quoted by the 'chlorine is bad for you, don't put it in your pool' camp. They really are meaningless when it comes to pool sanitation, however. There has been much discussion of this on this and other forums in the past so it is really an old topic. You might want to use the seach feature and see what has been said previousloy by Ben and others from before you became more active in the forum.

Monochloramine is a nitorgen containing compound and as such, it is consumed by the algae which is why it is effective at killing algae compared to chlorine. Patents have even been taken out based on this. Pool service techs used to use anhydrous ammonia added to a pool in conjunction with shocking to kill algae by this method. Today various orgainic ammonia products such as Yellow Out by Coral Seas are based on this technique. It is fast and effective at killing algae but the drawback is the fact that FC drops to 0 ppm while TC is high until all the chloramine is destroyed. However, this does happen rather quickly in an outdoor pool with repeated shocking so it is not a major issue as long as the pool is not overdosed with the ammonia source.

As far as pH effects on hypochlouous acid concentration in a stabilized pool, that is an entirely different subject that I was referring to. Once CYA enters the equation the effect of pH on HOCl and OCl- concentrations basically goes out the window. By keeping the pH high you favor the formation of monochloramine (as opposed to other chloramine species) which will help and not hinder the killing of algae.

Moderators, this thread hijack would probably be better if moved to the China shop since the matierial is not relevant to the OP's question but is a side tangent by smallpooldad.

[AnnaK]

My understanding of mustard algae is that it tends to creep up on the sides of the pool. Your stuff appears to settle in and get trapped by the small creases in the liner.

You said the pool hasn't been used or vacuumed in a week which is a good long time for dirt and dust to collect on the bottom.

I'm all for brushing to keep the material in solution with the pump running. Since you can't test for CCs you could try an alternate method: test FC after the sun is off the water and test again early in the morning. If the difference is zero then there's nothing in the water for the chlorine to act on.

AnnaK

[waterbear]

My understanding of mustard algae is that it tends to creep up on the sides of the pool. Your stuff appears to settle in and get trapped by the small creases in the liner.

You said the pool hasn't been used or vacuumed in a week which is a good long time for dirt and dust to collect on the bottom.



AnnaK

Anna, Good Catch!

Mustard will not just settle in the cracks but ususally covers the sides and bottom, particulalrly in the shady parts of the pool. If you brush it away it's usually back in a few hours. This is not what you have been describing.
Not vacuuming for a week will allow a lot of dirt to collect in the cracks. I suspect that is what is going on here.

[denanbob]

This is interesting because the chlorine does not seem to be budging at all (not losing any). I cannot get an accurate chlorine reading. I have the WalMart test and when I test chlorine, it is a dark dark orange color. So I tried last night to dilute it until it turned yellow and it never did. It went straight from orange to clear so I can't tell what the chlorine reading is. As of Monday when my chlorine was 2, I've added a total of 5 3qt. jugs of 6% bleach which would equal almost 4 gallons which SHOULD have raised my chlorine to a total of 26. However, even when I dilute up to 7 times (which if the color was equal at the 5 line would be 35 chlorine) it is still dark orange. So is my chlorine even higher than 35? Yikes I hope not. The stuff had returned yesterday although not as heavy and I brushed it to mix it back up with the chlorine. There was some yellow staining on the walls here and there, but mostly this stuff in my original picture pretty much concentrated to one area of the pool (NOT the part in the most shade). I haven't kept up with the discussions between smallpooldad and waterbear because it is beyond my level of comprehension (LOL), but just wanted to update everyone since you all were kind enough to help me with my problem (even though the verdict is still up in the air as to what the problem actually IS).

[waterbear]

It's not mustard. Mustard doesn't settle in the cracks. Also, when you brush or vacuum it it's back in place in about an hour or two. I suspect it's just normal junk from not vacuuming, possibly some pollen mixed in to give it color.
I would strongly suggest getting a better test kit that uses FAS-DPD chlorine testing such as a Taylor K-2006 or a TF100 from TF Test Kits. (google them, it's owned by someone who is a member here but I don't think he is active on this particular forum much but he is busy on another pool forum.)

[chem geek]

I've responded to smallpooldad's post above in this thread in The China Shop.

[smallpooldad]

Question posted here:

http://www.poolforum.com/pf2/showthr...6952#post56952