It's good to filter out the particles.
I don't think there's anything wrong with your brew.
The cold water one may not be as potent from the sounds of it.
75/4 sounds like the perfect dose so you're on the right track there.
You can buy big cotton tea bags and just stuff it all in there and brew next time.
It's good to let the brew sit in the fridge and let the particles drop to the bottom so you can pour off the liquid, save the liquid, and discard the decanted plant material.
It may seem tricky at first but after a few times this will be second nature.
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