This was a reply to a reader who wanted to use an outside reactor to operate his RowaPhos (a chemical to reduce Phospates in the Aquarium)a very expensive option compared to the instruction I give below:
You would be better off doing what I do (and it`s cheaper) get a slim plastic box that will fit inside your filter, if you have not got one, there are loads of websites or shops that may have the size you want, then drill or burn with a piece of wire, some holes in it top and bottom, but not too big, as it has to hold your Rowaphos & keep it in without stopping water flow. This acts like some filter box`s that hold filter ceramics. It will act just like the object you wish to buy, without all the expence! the Rowaphos will move about in the box as long as you do not pack too tightly. TIP: If you want a close fit in the filter, use a hot melt gun around the sides to shape it to be a close fit, you can always trim it with a knife.
