I'm not sure what to tell you, every once in a blue moon someone makes a thread about how cloudy their water becomes after feeding (brand xyz) and yet the vast majority of MFKers never have this issue, with the same food.
There's no plausible reason that I can think of that would have NLS .5 mm or 1mm pellets trigger that kind of cloudiness in ones tank with those fish, especially when only feeding a couple of pinches - other than your bio-bacteria is not fully established yet and therefore cannot handle the payload during feeding.
There's really no other explanation that I can think of.
This is a rather new set up, and if your filters didn't come off of fully mature established tanks that you already had set up, I'm guessing that what you are seeing directly after feeding is a small ammonia spike, which is is causing a mini bacteria bloom.
Your water looked pretty cloudy in these previous pics as well, when you were just first setting the tank up.
http://www.monsterfishkeepers.com/f...68641-How-would-you-stock-this-aquascape-125g
Or was that just from the sand getting stirred up right before those pics & vid were taken?
Personally I think that your problem will resolve itself in the near future when your tank becomes balanced.