Ria

~~ Traditionally, August was an off-peak time, but with school holidays now being staggered we no longer have an off-peak season. Because of this prices don’t vary much with the seasons.
However, certain resorts (on both the Gold Coast and the Sunshine Coast) offer a weekend/3day deal.

~~ But if you’re willing to come a little further south over the border, try the Kingscliff area.
Kingscliff is only about ten minutes from South Tweed Heads so you are close to Coolangatta and another 30minutes puts you in Surfers Paradise!
If you’re flying in, Kingscliff is only about 15 minutes to the Gold Coast Airport.
Kingscliff now has several nice resorts, and the town’s main thoroughfare has many great outdoor eateries.
You can just wander the beachfront and relax at any of the cafes.
My personal favourite is the Choux Box.
Kingscliff is extremely laid back and (despite the high-rises taking hold) has retained it’s beach-village atmosphere.
The Cudgen Creek flows into the Pacific there and it is perfect for snorkling. It is popular with both local and holidaying families.

This site has accommodation, restaurants and things to do & see around Kingscliff:

~~ I think you would like Coolangatta too.
Not as hectic as Surfers but has many fine resorts, some nightlife, many eateries, perfect beach. And the Tweed River is another snorkling paradise.
You often catch dolphins at play in the river – very cool.
Coolangatta is also a place that hangs onto a country town atmosphere while multi-storey resorts pop up overnight.
May I suggest the Twin Towns Resort for accommodation, located smack-dang on the border, with amazing views of the coastline and a covered walkway across to the RSL Club.
This is the resort’s website:

Wherever you choose to go, enjoy your break.