Pumps to get oxygen back into a lake where thousands of fish perished last week is not the solution to a much larger problem, a lake user has said.

Plans to re-develop the lake by the fishing club the Wandle Piscators could be altered after the incident where horrified children saw hundreds of fish of all sizes dead and dying around Cannon Hill Common lake in Wimbledon Chase.

An estimate at the time put the number of dead fish at 1,400 but it now known to be 2,000, with stocks set to be replenished by the Environment Agency (EA), Merton Council and an angling club soon.

The EA said a drop in oxygen levels had been caused by algal bloom dieback and high temperatures resulted in the fish deaths.

William Tall, who is the senior vice president of the Wandle Piscators said more needs to be done for a long term solution.

Mr Tall said: "The lake has a lot of environmental pressure on it because of the trees and bushes around it.

Wimbledon Guardian:

"Leaves rot away in the water and feed algae which take away the oxygen.

"A sustainable solution is tackling the problem not just adding another aerator."

He said left-over bread from people feeding the ducks contributes to the nutrients in the lake and it is about getting the balance right.

Bread bags and leaves get stuck in the aerator, causing it to stop working, Mr Tall added.

Objectives for the lake re-development include installation of fishing platforms to be used by families and disabled people, improvements of the lake habitat and fishery stock and reducing the amount of anti-social behaviour in the area. The ideas will need to be looked at again after the incident.

The platforms could take two to three years to install, and have been received well by the EA, Friends of Cannon Hill Common and the council, according to the group. Officers from the EA have been at the lake to collect the remaining dead fish, many of which had been eaten by gulls, after the incident a couple of weeks ago.

Since then ducks and coots appear to be unaffected by the tragedy and have been spotted cruising around the lake by residents.

Speaking about the action the EA took as a result, a spokesperson said: "Dissolved oxygen readings in the area we treated with peroxide are now around 100 per cent, so the combination of peroxide treatment and the club’s mechanical aerator have been very successful. "We have offered a post mortality fish stock assessment to the angling club and London Borough of Merton and we will work with them to establish a new sustainable fishery."