How much is the TDS increased if Borax is added to 50 ppm

[smallpooldad]

Well it was not black or mustard algae.

Chlorine remained stable over night, for 3 days, at 40 ppm, pumped it back up to 40 ppm every night for 3 nights. So me thinks maybe adding Yellow Treat (Sodium Bromide) will do the trick, as these two types of algae are thought to be chlorine resistant.

Added 5 oz of Yellow Treat and pretty much nothing happened. Chlorine got used up and went down to 30 from there it has been a very slow descent to 12 ppm of chlorine. At 12 ppm of chlorine last night and 12 ppm chlorine this afternoon at 3 pm, it has been very overcast and humid today and yesterday.

The stains were primarily lightened when I initially added Borax, and then when I scrubbed with a wire brush. However, since then really no change still some light stains in the plaster maybe from 9 years of not knowing the Pool Forum. Why did you not call me in those 9 years?

The Borate is around 70 ppm and this is why the chlorine stubbornly refuses to go down any faster. What are your opinions?

If that is the case, I will report back, and then maybe Chem Geek you have found the answer to controlling chlorine use.

Chem Geek, if this is true then be careful if you see any guys dressed in black suits with violin cases and wearing a yellow Wal-Mart smock!

Finally the pool is crystal clear, clearer than it has ever been.

Here are the figures:

Cl 12 ppm
Alk 80 ppm
pH 7.4 ppm (seems to be stuck at this number/has not moved for days and yes I neutralized the chlorine for a good reading)
Calcium 350 ppm
CyA 50 ppm
TDS 740 ppm

Aloha and thank you one and all.

[smallpooldad]

Now I'm worried, just read your other reply on the TGT Debate stating that bromide never goes away. If this is so why is the Chlorine holding? Or, is it possible the bromate can get eaten up?

Looking forward to your reply.


Aloha

[chem geek]

Bromide (and bromates) and Borates are two completely different things. You have Borate, Boric Acid, Borax or Boron (take your pick as all terms could be used) in your pool, not Bromide or Bromates. I know this is confusing -- just focus on the first three letters -- Bor... is the stuff that helps prevent and kill algae and helps stabilize pH (and makes the pool sparkle) while Bro... is the alternative sanitizer to chlorine, often used in hot tubs, and should not be used in a pool unless you permanently want your pool to use Bro... (i.e. you have to drain your pool to remove Bro...).

The high level of Borates in your pool will help prevent algae and kill some of it as well. That means that the chlorine won't have to so chlorine usage will be less because of it, at least in terms of killing new algae. However, the chlorine will still try to oxidize the algae that is there even if much of it is dead and could get somewhat consumed because of that. If you find that it isn't dropping, then the algae is dead and the easy-to-oxidize stuff has been taken care of so all that is left is to filter out the dead solid cells and you are done. It sounds like your water finally turned clear so that's that!

As for recommending anything different than chlorine, I would say that isn't true. Though the Borates (Borax) may have helped speed up the killing of the algae, the decision to use Borates is a yes/no decision for whether you want your pool to always have borates or not. You cannot get rid of the borates in your pool except by dilution (not that you'd want to get rid of Borates as they generally do no harm, but I suppose if you built up more than 100 ppm you might want to dilute to cut back). So using Borates isn't something to tell people to do when they have an algae problem -- it's a separate decision and yes, if they already decided to use Borates then it appears that they will have less problems with algae.

And yes, using Borates reduces chlorine consumption (as waterbear found to be true), but that won't put Wal-Mart out of business. You'll just need to buy less chlorine...I'm sure Sam's folks will find other things to sell to you.

Richard

[smallpooldad]

Thank you for your reply.

In the last message above I should have typed "is it possible the bromide", sorry for the confusion.

Until Wal-Mart sells "Marmite", Britain's gift to the culinary world (Vegemite in Australia) I will not be going back, except for chlorine.

But I did put Yellow Treat 4.5 oz (Sodium Bromide) in the pool. Will this, or has this gone away, due to the large amount of chlorine I used? Or do I have to drain it? Please say no.

Lastly I will not add any more Borax (Borate) to the pool until it shows 50 ppm. Now have the AqauCheck test strips, they arrived two days ago.

Aloha from a hot and humid Hawaii that only the mosquitos could love today.

[chem geek]

But I did put Yellow Treat 4.5 oz (Sodium Bromide) in the pool. Will this, or has this gone away, due to the large amount of chlorine I used? Or do I have to drain it? Please say no.

Well, I'm sorry to tell you this, but the Sodium Bromide indeed adds Bromide to the pool and the disinfecting chlorine (HOCl) in your pool will "reactivate" the bromide (Br-) to hydrobromous acid (HOBr) converting the disinfecting chlorine (HOCl) into chloride (Cl-). And unfortunately there isn't much you can do to get rid of it. It's not horrible having the bromide in your pool, it just means that you've got a secondary sanitizer that is less effective than chlorine and that whenever that sanitizer gets used, the chlorine will get used up to regenerate it. Not terrible, but not great either.

Perhaps someone else can tell you more and maybe find a way to get rid of the bromide/hypobromous acid or give you better news than I just did.

Richard

[waterbear]

If my understanding of the chemistry involved is correct then inorgainic sodium bromide will eventually form bromates (which do not 'reactivate' into hypobromous acid) and then you will have a chorine pool again. It is the organic form of bromine found in bromime tabs that contain dimethylhydaytoin that sticks around forever.
Ben (PoolDoc) summed it up on this PoolSolutions page
http://www.poolsolutions.com/tips/tip10.html

Hope this helps.

[chem geek]

Thanks Evan. OK, according to Ben's post it sounds like the bromide can be removed with shocking on a sunny day, perhaps repeatedly. The organic form would have the organic part stick around and be hard to get rid of, but the Yellow Treat was just sodium bromide so didn't have the organic part. So that's good news.

So, smallpooldad, the fact that you were at high shock values after adding Yellow Treat probably means you got rid of most or all of your bromide, especially if your pool had exposure to sunlight. Wheh! That was a close call!

Richard