Based on color, those are definitely not caapi alkaloids.
You mentioned that your tap water is pH 9.1. Maybe there’s something in your tap water that’s affecting the results? A combination of minerals or ???
I’d suggest trying an extraction – from beginning to end – with distilled water. That way you can at least rule out any problems caused by water.
Since you’re having problems, I suggest you experiment with smaller amounts until you get it right (maybe 50g extractions).
Don’t give up!
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