do you want a video? i can make one.
I use the plastic siphons , I start by very soft thumping on the gravel (enuf the disturb the settled dirt), the debris/dirt lifts off, i lift off the siphon and it sucks the floating debris/dirt, as i see that clear, i move to next patch, the bucket is full of dirt/debris. next bucket has brownish water and not that much dirt. so after siphoning off 50% water, i refill it with the 1 day stale de-chlorinated water.
I do not STIR the the gravel AT ALL. that just lifts the nutrients out of amazonia soil and damages the roots.