Lake Ainsworth also known as Tea Tree Lake is an absolute natural wonder.
I highly suggest walking along the main beach and finding your way towards the lake where the ocean meets the lake.
You'll see the clear ocean water turn into a gold, then a deep red colour and you'll know your on the right path.
Tea Tree Lake has a wonderfully unique colour, varying hues of yellow and red, as the water is stained from the many tea trees that have fallen & decomposed in the water, it has made the lake smell sweetly of teatree, and the water is amazing for your skin.
The Bundjalung Aborigines were the first to use the Tea Tree plant for medical reasons, apparently they would bathe here often. They would crush up the Tea Tree leaves and rub into skin for burns, irritations etc. there is a lot of stories behind this lake in particular depending on who you ask.
I highly recommend having a swim here, don't be off put by some of the squishy parts on the lakes bed, it's all part of the wonderful natural process.