I did my first extraction a few weeks ago using 50g of powdered MHRB. Not sure the exact tek I used but I’ll explain it in detail momentarily.
Not having a scale at the time but comparing to my current amount I can estimate my first yield was 400mg.
This time, being my second extraction I did the exact same steps as last time, and woke up this morning to a very disappointing 150mg from 50g of MHRB.
My processes is as follows.

50g MHRB
750ml Distilled Water
50g NaOH

Allowed all that to sit for about an hour and a half after shaking for a while.
I added 50ml of naphtha and mixed gently by turning the bottle over for about a minute.
Set on a hot plate and allowed to separate. This process was repeated about 5 times.

Naphtha layer was separated into a mason jar.
A solution of 50ml of water and sodium carbonate was prepared.
5ml was added to the naphtha later and shaken.
I then separated the two and discarded the water layer.
I repeated this process twice using 25ml of plain distilled water.

After the wash the naphtha was placed in a Pyrex dish and put in the freezer overnight.

I repeated all of this using fresh naphtha each time for a total of 3 pulls
Since I only have one Pyrex dish I placed the 2nd and 3rd pulls in mason jars and then in the freezer.
First pull was 150mg
Second was redisolved and placed in the dish so I could scrape it up properly and I’m waiting on it now.
The third pull was completely empty.

After all this I’m estimating only 200mg as opposed to last times 400mg.
What am I doing wrong? And why is my yield this time so much lower?
Any advice would be great. Thank you!

-The Guardian

Just a simple question. Did you use the same type of bark?

There are so many teks outlined in the Nexus wiki, Cyb's hybrid A/B Salt tek I find absolutely fantastic, great fun to do and rewarding results

I couldn’t find the source I first used. So I used another. Could that have something to do with it? It’s all MHRB so I wouldn’t think it would cause that big of a yield difference.
Also I still have the NaOH solution, is there a way I could add stuff and do more pulls to get more spice? I mean I’m happy to have my 150 (which finalized to 200 after the second pull) but I do feel like I wasted bark and could’ve gotten way more out it.

Check out Cyb's A/B hybrid salt tek in the wiki...add salt and heat in a water bath then cool to 40 c then pull again...

Thanks so much I'll give it a go and see what happens.
The solution has been sitting for a few days, will that matter?

The sodium carbonate wash is notorious for eating spice, you might want to skip that.

The source plays a huge part! It can affect the yield everywhere from 0-100%!

Like mentioned above adding salt and heat use to push a little bit more out of the bark.

Enjoy!

Time isn't an issue, good luck and travel safely

do more pulls. obviously different batches of bark have different potency though.

Added salt and heat and all that and did another pull skipping the polar wash.
Still nothing :/
Perhaps it was just a bad batch

I'll try again soon!