I don't know where you live, but I'm in the US, and I had to order my sodium hydroxide online with a prepaid card, got 2 lbs of food grade lye, and really, it's more than I'll use in years. I wouldn't really want to use 98% sodium hydroxide, 2% is alot when dealing with possibly dangerous chemicals in the mix.

I don't know what tek you used, I do a/b extractions personally, and you just have to be thorough while boiling, and pulling with naptha. I've heard of people doing 10 pulls and still getting more, I usually do 5 pulls on mine.

Also, you may not have basified the mixture enough, that was my problem on my first extraction, and I ended up with weak brown goop. I never got a ph meter, I just add twice the reccomended amount of lye, and it works out great.

Hope this helped. good luck with future extractions.