I pulled this text from another website
"Here's a sure-fire way to judge blotter. Put a blotter dose at the bottom
of a small test tube, and squirt in a few ml. of water, while observing it
under a long-wave blacklight. Room lights should be off. LSD is very
soluble in water, and in solution it fluoresces a brilliant blue-white
colour under blacklight illumination. AS a reference, quinine, as in the
tonic or quinine water used to make gin & tonic, fluoresces the same color.

Blotter paper can be stored for long periods in an airtight bottle in a
freezer. It will decompose slowly, but the decomposition products are not
harmful or active in the doses produced by the decomposition. AND, if you
disslove off the active LSD in water as above and then pull out the
blotter, you will see that the dark stain mostly remians on the paper, thus
the water solution has purified the dose to a significant extent. Of
course, the amount dissolved will not be optimum, so it may be necessry to
use tPeter Webster or even more to arrive at a full dose. With some
practice, using the same test tube size and amount of water, the brightness
of the fluoresence will even give a reasonable test of the strength. Bright
blue fluoresence is what you are looking for, if it looks only pale yellow,
there is not much left."

notice he said "long wave blacklight"
short wave is like a standard bulb blacklight and therefore will not work