Frequency for adding Sodium Dichlor ?

I have a new 37,000 gallon pool. I am using Sodium Dichlor as sanitizer with Nature 2 system. I was told to put 32 oz (2 lbs) in the skimmer twice a week which I did today. Afterwards the pool smelled strongly of chlorine and irritated my eyes a bit. I tested the pool for chlorine and it went off scale on high side. My question is how does the level of Chlorine (ppm) change through time (days 0-4) ? Would I be better off adding Dichlor every two days, or even daily to minimize "spikes" in chlorine levels?

I think you will find that most members of this forum, me included, would recommend getting rid of the Nature 2 (or at least NEVER letting your free chlorine drop below 2 ppm! Recent studies on kill times for water borne pathogens done by the Austrailian government support this! They now require all copper/silver systems, including Nature 2 be used with NORMAL and NOT reduced Free Chlorine levels).
Also, using bleach (same as liquid chlorine) for chlorination is cheaper and will not cause your pool to be overstabilized. You need to maintain a stabililzer level of 30-50 ppm.

Thanks Bear. Do you have any further information (internet link, etc.) on the Australian govt study on water borne pathogens and need to run Nature 2 system at higher chlorine levels. I am new to this and my pool guy had indicated I should keep chlorine no greater than 1.0 ppm for ideal operation with Nature 2. thanks

This should do for starters

http://www.apvma.gov.au/qa/poolspa_FAQ_May2005.shtml
http://www.apvma.gov.au/qa/poolspa_recallupdate.shtml
http://www.apvma.gov.au/qa/poolspa_Q&A.shtml

Thanks WB. Given my new pool has Nature2 am I best off keeping chlorine > 2 ppm or just abandoning (in favor of what??). Thanks for any suggestions.

If it were my pool I would ditch the N2 and just use bleach or, better yet, install a SWG.

I was told the same for pool care by the store and after finding the form and thinking about it I ended up ditching the N2 system. If you are in for a read about it you can take a gander here.
http://www.poolforum.com/pf2/showthread.php?t=405
I was out about $80 to $90 a month on chem and if I used the N2 about $110 a year for the N2 before finding the forum. Last month I spent $29 on chems for the pool. Most pool stores are out to dig deep in to YOUR pockets and sell you magical products. I was pool stored for $425 when I bought my pool.:mad: Listen to the pros here they know what they are talking about. They will save you money and give you great advice to have great water.
Waterbear as useual I dont include you in the above statement.:D
Steve