Yeast Harvesting Question

Twice I have harvested yeast and after putting the trub in cold water and swirling it around a few times, I still don't get the division of yeast on top, thin line and dark trub on bottom. Maybe I just screen out so much of the hops and grain leavings that I don't have the bottom layers.
Mine just turns into a brownish liquid and finally after a day, the brownish wort is on top of a layer of very light brown or tan layer of yeast (I presume) on the bottom.
Question: Am I removing so much other material when I strain the boiled wort that the only thing left in the bottom of my primary is yeast and a little wort and no trub to speak of?

I think you need to slow down a bit...relax, have a homebrew.

After you've racked your beer, swirl the primary a bit to mix the remaining beer with the yeast cake on the bottom. Break it up really well.

Depending how much you want to save, use 1 or 2 growlers. Pour about 1/2 gal of trub into a sanitized growler. Add about 2 C of sterilized water into the growler and swirl some more.

After about 10 minutes or so most of the trub will settle out. Pour off the liquid into another sanitized growler. (Re-sanitize the original growler so you can use it again).

The "muddy water" is your yeast in suspension. You need to seperate the gunk from your yeast. This is the whole purpose of the experiment.

Wait another 10-30 minutes and observe if any more garbage has fallen out. If so, pour off the liquid into aother growler (the 1st one again).

At this point you can put it in the fridge. The coldness along with time will allow the yeast to fall out of suspension.

Prior to use you can either pour off most of the remaining liquid leaving only yeast behind. You can add 1 C of cooled sterilized water to remix the yeast
for your starter.

I like to keep mine out of the fridge because I like repeating this process until I have clean yeast. This may be considered overkill by many, so it's not necessary.

Good luck.