essexandy
The Lake Governor
What I do is a bit revolutionary, but here goes, I buy products and read the info on the label and then stick to their advise, no watering down (unless recommended) and no weird additives, this has almost always worked for me (apart from that Sika rubbish and odd problems with BG) as the companies making these products tend to know best and if something does go wrong it's not your fault.