"I've tried La-Co & the Fernox stuff and both are rubbish, what you need is a dirty great pot of the yellow Powerflow flux. It works a treat everytime. It would have got 5/5 on features if it had a little brush with it or Plumbfix sold them but outstanding stuff anyway!"
"The flux works really well but a little different to what I’m used to. It has the consistency of gritty tomato ketchup, only in white. What I really dislike is the tub it comes in. It’s one of those containers that no matter how careful you are, you will have some of the contents oozing out from under the lid as you screw it back on. For the price, I would expect better, especially from Fernox."