Lady Gaga has reportedly installed a 'massive' fish tank to entertain herself while she recuperates from surgery.

The American singer has cancelled the final 21 dates of her Born This Way Ball tour after sustaining synovitis - a severe inflammation of joints - and a tear in her right hip.

She quickly underwent an operation to repair the condition and is now at home recovering.

British newspaper The Sun reports that Gaga has been ordered to obey 'strict downtime' while her hip heels.

To keep herself visually stimulated, the singer apparently purchased a fish tank filled with 27 koi carp.

The massive, colourful fish are said to be a very welcome addition to her interior design and Gaga did not worry about the price.

'Gaga said she'd had a dream about the fish so she had her team source some koi and set up a massive tank,' a source revealed to the publication.

'The whole exercise cost over £40,000, which is a lot to most people but small change to her.'

Gaga apologised to her fans for having to cancel the rest of her tour dates, explaining she suffered the injury some time ago but had been attempting to cover it up to avoid disappointing them.

Last month she tweeted a picture of her wheelchair, which she has named Emma.