There is an error in my post #4.
3. Capacity is (0.85 x (.3 ^2) x "Pi") = (approximately) 240 litres. Usable hot capacity probably 3/4 of this, say 180 litres is WRONG. It should read:
3. Capacity is (0.85 x (.15 ^2) x "Pi") = (approximately) 60 litres. Usable hot capacity probably 3/4 of this, say 45 litres. (Volume = Height x RADIUS ^2 x Pi. I used the diameter)
On that basis, if the measurements are correct, the tank is too small for more than one partial bath from a single re-heat.
3. Capacity is (0.85 x (.3 ^2) x "Pi") = (approximately) 240 litres. Usable hot capacity probably 3/4 of this, say 180 litres is WRONG. It should read:
3. Capacity is (0.85 x (.15 ^2) x "Pi") = (approximately) 60 litres. Usable hot capacity probably 3/4 of this, say 45 litres. (Volume = Height x RADIUS ^2 x Pi. I used the diameter)
On that basis, if the measurements are correct, the tank is too small for more than one partial bath from a single re-heat.