instead of straining, try letting it settle and scooping some clear liquid from just under the surface. You might have to skim off some scum. One of my batches keeps a foamy scum on top, the other-not so much. But now they're producing the same color--about 2 months in. It' takes at least 3 weeks to get any good color in my very limited experience.
Just leave the precipitate on the bottom.
And it takes a few hours/overnight for color to really show in my wood.