We know from tests that the oxygen levels in the lake had dropped considerably, so the Environment Agency is recirculating water into the lake in an effort to stabilize oxygen levels.
Low oxygen levels could be due to a number of factors linked to environmental conditions such as decomposing algae or sediment stirred up by recent storms.
The surviving fish now have areas which are oxygenated and we will continue to work with the Environment Agency to make sure that oxygen levels stay at the required level.
Although tests for blue-green algae have returned negative, we would still like to remind people that there is no fishing on the lake until further notice to allow for the clean-up operation."
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The dad of Luke Jenkins, who died at Bristol Royal Hospital's children's cardiac unit labelled an NHS England review a 'tick-box exercise'.
It's a cloudy offering with drizzle in places today - although some maybe lucky and escape.
The cardiac service at Bristol Children's Hospital was blighted by understaffing and poor communication, according to a review out today.