Aluminium does under go oxidation, although it is white. Unlike iron oxidation which is orange. If the tile is designed for use in a wet area it is probably coated or anodised to prevent white oxidation. Check if cleaning will be a hassle (risk stripping the coating).

Are you looking forward for a new installer or advice?

Bathroom renos can be daunting as there are many things to consider and usually the space can be limiting. Free standing baths are stunning and come in many shapes and sizes. You have mentioned that you and the boys will use the bath, ensure you factor in the "users" height as this will determine the bath size and depth. Firstly is the plumbing remaining in the same position? Floor mounted bath mixers can be installed with a concealed under floor box or the above floor connection method. The concealed box method is advisable before the flooring is installed, and has the benefit of a lower profile floor plate, which is preferred. The above floor method may be done where the first approach is not possible. Free standing bath mixers visually create an impact when paired with the freestanding tub, ensure you have enough room around the tub as it will be difficult to clean if it sits too close to walls and or vanities etc..many freestanding bath mixers offer functional hand showers as well as the spout, ideal for washing soap out of kids hair. Would love to see a lay out of your bathroom to assist with tap ware placement. Good luck with your bathroom renovations, always happy to assist you. Carmen Collaborative Interiors

I would check with your builder about re-using second-hand products as it may have warranty implications for your new home. Be sure you understand about tiling lips for bathtubs as it will affect your placement, waterproofing and tiling. I would not re-use, but sell it on ebay and buy a new equivalent rather then spending money on re-enamelling and re-installing. Best of luck, Dr Retro of Dr Retro House Calls