First, and unmentioned in Susan Watts's article, is that the zoo would cease to be part of the Zoological Society of London if the Laing proposal were accepted. This is not an acceptable option to many fellows of the society, since it would mean that the most famous part of the society would be lost and the zoo's aims and purposes would change from a serious conservation-based activity to an essentially commercial entertainment centre.
Second, the spending of the very large amount of money required in order to build and stock such an aquarium is a quite unjustified activity for the zoo, whose limited funds must be used for conservation projects and for the instruction of the public in serious conservation endeavours. The only way such an aquarium would be an acceptable proposal for the zoo is for it to be funded from outside sources with no strings attached, in other words, no loss of control of the zoo by the society.
I totally oppose the Laing proposal, since its purpose is essentially to make money from the zoo. This is not compatible with the aims of the Zoological Society, which is a registered charity. David Laing's reference to London Zoo as a 'leisure site' shows that his proposal is at odds with the raison d'etre of the zoo and the society.
Little Eversden, Cambridgeshire