Always add ResClear to the water first, even before Silicate 7.8. ResClear will maintain a clean reservoir free of bacteria, fungi, algae/slime for up to 14 days at which point it should be replenished. For this reason we generally use this product for the beginning of root development to build a good water immersed root system for microbes survive on prior to converting to Root Assist. You may use ResClear all the way through harvest if desired.
After 9 days of vegetative growth ResClear continues to actively keep the roots white, while maintaining a clear and residue free reservoir.
At day 14 the reservoir is refreshed with ResClear and the air stone untouched still retains a brand new appearance.