Which ONE of the following may cause low levels of oxygen in an enclosed tank? Give ONE answer
A Atmospheric pressure
B Convex walls
C Moss and algae
D Rust
Answer:D
Which ONE of the following may cause low levels of oxygen in an enclosed tank? Give ONE answer
A Atmospheric pressure B Convex walls C Moss and algae D Rust
Explanation: Rust (oxidisation) can deplete oxygen levels in an enclosed space.