Thanks. I have used deep tanks with floating lids, but I now used daylight tanks, working from a 1 liter bottle of stock and another of replenisher. I put the replenisher in the stock bottle and then return the used developer, filling it to the top. I'm used to long-term muddy looking developer and I agree, it does not hurt. The problem I'm having is floating particles in the developer, starting with the first replenishment. I have filtered the entire bottle and they return. The dry chemicals are kept in sealed containers and I use distilled water to mix them. The bottles are brown glass.