You can't really tell. You have to estimate based on water replacement. You have to add more sodium bromide to make up any lost to splash out, backwashing etc. It doesn't hurt to have too much sodium bromide, so you can add extra just to be sure.
Yes, I think that that should give better results than using tabs.Below is a reference to the method.AClogston said:So to implement this in a pool that's already been using bromine could one just add sodium bromide periodically while constantly feeding liquid chlorine with a peri pump at lower rates?
One common method of producing bromine in pool water involves the addition to the water of sodium or potassium bromide in conjunction with an oxidizer such as sodium hypochlorite or monopotassium persulphate. These substances are available as solutions and they are readily dosed into pool water.
Method 2
The addition of sodium bromide together with an oxidizer such as sodium hypochlorite to the pool water.
Sodium bromide and sodium hypochlorite are supplied commercially as solutions.http://www.health.sa.gov.au/pehs/public ... romine.pdf
There are several possibilities that could cause swimmer irritation. It could be an adverse reaction to the DMH. It might be that excessive DMH is preventing the bromine from properly sanitizing the water, or it might be something else. I agree that minimizing DMH is a good idea.AClogston said:While it's only happened once or twice, I have had complaints of minor skin irritation (only in the bromine pool/spa) and now I'm led to believe eliminating DMH would be a step toward eliminating them entirely.
2.4 ounces of bromine tabs added to 24,000 gallons will add 1 ppm of bromine, 0.4 ppm of DMH and 0.25 ppm of bromide.AClogston said:What kind of a dosing schedule would I be looking at with the sodium bromide? My usual dosage for bromine is 2 bags (roughly 60 1" tabs each at 0.5 oz./tab = 60 oz. = 3.75 lbs) every 10-14 days, depending on bather loads, and I like to keep it at around 6ppm. As far as water replacement, I usually refill about ¾-1" every week (~381-510ish gallons), not taking backwashing into account which is usually done about once or twice a month, as needed.
Any ballpark estimates? Also, with those numbers, would you have a rough estimate of the amount of DMH currently in the pool? Thanks a lot, this is great info!
JamesW said:5.5 ounces per 1,000 gallons will give you a sodium bromide level of 40 ppm. Sodium bromide is 22.4 % sodium and 77.6 % bromide. 5.5 ounces of sodium bromide per 1,000 gallons will give you 31 ppm of bromide ions, which can be converted into up to 62 ppm of bromine.
The minimum bromide should always be at least half of the maximum bromine level you will want to achieve.
Here is an example: If your bromide level were 5 ppm and you added 220 ounces of 12 % liquid chlorine, then 110 ounces of the liquid chlorine would convert all of the bromide into 10 ppm bromine and the rest of the 110 ounces of the liquid chlorine would create 4.44 ppm of chlorine.