Quick question. I have a black plastic domestic water tank sitting on top of a structure that holds an old steel watertank that the black plastic one has replaced. I want to leave the black plastic one in situ by building a support structure and pulling the old tank and structure out from below.The struture is in a hotpress with one wall made of brick (red house brick, no cavity) and the other side plaster board. I was thinking of fixing a timber support to the brick wall with rawl bolts from which i could run heavy timers below the tank to a vertical timber support on the plasterboard side that runs down to the floor (think 2 upside down Ls with the top of the upside down Ls supported by the brick/rawlbolt/timber support). What kind of rawl bolts would be sufficient to hold this kind of weight. The tank holds a couple of hundred litres of water. I would have to go into the wall as there is pipe work running along the bottom of the wall. All advice welcome (timber and fixings) and apologies for the long post.
Crude drawing attached.