You're using quite a lot of Lye in your mix.
I use 30g per 50g of bark. in around 600ml Water.
Also I use around 40ml Nap per pull.
25ml will saturate quickly and is hard to separate a thin layer.
Heat baths will make the nap more yellow (pulls more oils).
STB's tend to be more yellow anyway.
I have taken to Re-xing the gooey mix/xtals and am getting a much cleaner product.
If you are unsure of the re-x process...here is my method:
Put 20/30ml Solvent in small jam jar.
Boil water in a pan and sit a sieve on top (stops the manic bubbling)
Put jar in water (within the sieve) (just need water level 1/4 way up jar)
Rest the lid on the jar (do not screw shut...the pressure build up is extreme and may explode...not good!)
Bubble away for 5 mins (solvent with get nice and hot)
Put goo/mix in a small glass/shot glass
Turn off heat and Use Gloves to retrieve the jar...Pour hot solvent over the goo in the small glass
It will dissolve but sometimes needs to place the glass in the heat bath (not boiling) and stir for a while (I use an eyedropper to stir)
Leave for 5 mins
Take out of bath and notice the separation of oils and other gunk.
Carefully decant/pour/turkey baste the solvent into another clean glass (best to use a wide based glass (easier to scrape later). Careful not to get any oil/gunk.
The solvent may still be yellowish.
Leave to cool with tin foil as a lid (stops dust and hairs getting in) Room temp is fine (bout 1/2 hour.
Then put the glass and foil lid in the freezer and leave undisturbed for 18 hours minimum.
Take out and pour out the solvent (keep for further pulls).
Marvel at the crusty layer of much cleaner crystals coating the glass.
Now fan dry for 1/2 hour before scraping.
If you don't have a fan it may take a least a day to evap all the solvent. (Patience)
That's it...sounds a bit scary if its your 1st time but it's so easy once you've done it.
Hope this help you and others.
Pic included of a 1g Re-x dried
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Re-x 2 sml.jpg
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