Thanks for the video. That said, I'd say there are a few things going-on that call for improvements:
1. The circuit should employ some form of current(mAh) limiting - so as to comform to the size of the anode(dia. and wetted length). Otherwise, the anode will be over-driven(loaded) and you will end-up with bi-products such as the ones shown in the video. - NB. most simple generators using single electrode and cathode setups, will use no more than .75 - 2.5 mAh of current at any given time. The downside to this however, is that this increases production time as the circuit will now limit the rate of the ion production at the anode and into the solution.
2. Additionally, the anode would be better suited if it were formed in a U shape rather than with with an open ended electrode(as is shown), as this will eliminate the potential for what I'd call hot-spots - areas where the energy can concentrate
3. The addition and use of a stirrer would be greatly beneficial, as this will further reduce the formation of hot-spots as well as promote the equalization and dispersing of the particulate(in solution) during production.
4. And finally the final piece of advice toward matters would be to ensure that the Anode is very clean prior to processing, as dirt will greatly contribute to the formation of hot-spots during processing.
Therefore, a good rule of thumb in this case, is to polish the anode(rod) and keep it clean at all times - avoiding storing tarnished etc - as this will make cleaning much more difficult as time goes on.
Beyond this, I'd encourage you to actively take measures to avoid allowing the sludge to build-up(aggregate) too heavily on the cathode, as this will end-up in the solution and further affect the quality and stability of your CS.