well what kind of water you using.
are you using blood meal? i ask cuz some of that red shit looks chunky and a grow sponge shouldnt be leaving chunks of coloring.
if your water isnt filtered you may have high iron in your tap.
i used to live in a place where the water came from the tap clean, but if you left a glass of it out it turned nasty red and got a hard oil-esque shell on top.
leave a glass of whatever water out and see what happens. or start looking at your seals on things, sometimes they can degrade.