Group members also said the science used to help construct the draft rules was inconclusive and needed independent verification and peer review.
Regional council staff admitted the science was not perfect but was the best information they had to work with.
Mr Murray said the council had followed up on feedback from a meeting held in September which asked them to personally contact all those at the meeting, conduct individual site visits, hold information days and provide answers to Official Information Act requests.
He assured those present the council was not going to rush the process.
Regional council strategic development group manager Fiona McTavish said other issues brought up by Protect Rotorua were still being actioned, including further research into alum dosing of the lake, economic impacts and the formation of a new accord to bring all affected groups together.
Protect Rotorua spokeswoman Sharon Love said in an earlier statement that the group wanted to "be sure that landowners are encouraged to do what they can to farm sustainably and to make sure any rules for the lake will be cost effective and must benefit the lake".