How to add Borax

[chem geek]

Could I use United Chemical's Yellow Treat which contains 88.8% Sodium Bromide, to aid in the destruction of this algae, or is this a bad idea?

I understand that Bromide consumes large quantities of Chlorine but seems to be effective in treating mustard algae. Any idea on how much Chlorine might be used up over the week so I can stock up? And should I maintainance the level back to 40 as it is used up? Is it correct that the filter need to be going 24/7 for the entire process?

What level of nitrates are considered bad for a pool?

Lastly I have Great White 9500 Pool Cleaner that has brushes on it that sweeps the pool is this good enough to do the brushing that is required or would it be better to hand brush with a pole? If so how often, and are the nylon brushes good enough or do I need to get stainless steel brushes?

I would not use Yellow Treat or anything else other than Chlorine, at least initially. There are other threads in the Algae section that pretty much say everything is useless or certainly no more effective than chlorine except possibly PolyQuat 60% which is mostly for algae prevention and not elimination.

As you point out, Bromide gets activated to Bromine by Chlorine and is generally what is done in spas that use bromine. This is not something you want to do in pools. Once you've got the bromine in your pool, it will be hell to get it out as the chlorine will reactivate it -- so you will end up in a cycle of bromine disinfection, then chlorine reactivating it, with the net result that bromine will be doing some of the work from chlorine, BUT doesn't do as good a job (generally) which is why it takes more bromine to be as effective as chlorine. Bottom line, don't add bromine to your pool in any form (bromide or bromine). Note that Borates refer to Boron which is a completely different element than Bromine -- confusing, eh?

Yes, maintain the level of chlorine at 40 ppm as it gets used up. If your pool is exposed to strong sunlight, then it could use up to half the chlorine during the day so that would be 20 ppm, but the key to see if this is working is to see if it gets used up at night and if the algae appears to diminish. You could just get enough chlorine for a few days (60 ppm worth) and then see how your usage goes.

No idea on what level of nitrates is bad. I know that it's food for algae, but don't know what level starts to trigger significant algae. Perhaps someone else knows that.

Unless you have black algae, you shouldn't need anything more than nylon brushes. Perhaps before you get started too much on this, you should make sure you don't have black algae. Black algae will be deeply embedded into the plaster surface while mustard/yellow algae will be more like a powder. If you have black algae, then the high chlorine level is less important that continually brushing and knocking off the exposed heads of the algae. Some people scrape the black algae with a Tri-Chlor tablet since this is both acidic and high chlorine (though bound to CYA so I somewhat question that) that black algae does not like. I think your overall high chlorine level plus scraping should be fine, even if this is black algae.

Since you seem fairly certain that whatever you have is algae, you should probably post in the Algae section and have Marie comment since she is the expert in that area. You can link to your post in this thread as a reference. She can probably refer you to pictures or ask you questions to identify exactly what it is that you have and how to treat it.

Richard