Hey Paul, check out a place called ecooutdoors.com.au for inspiration. I'm not sure if they're up your way but I'm sure you could get materials shipped. They have such a beautiful store with brilliant ideas. I'd be considering a stone that is cool under foot on hot Brisbane days and at least 30mm thick. You have an oval-ish shaped pool so you might consider a small coping stone to replace the brick then move on to a larger stone instead of the dated pebble, maybe a 'cush' limestone or go a bit glam and do a herringbone pattern with the right stone. Good Luck.

Sorry but the water line blue and white flowery tiles look old fashioned and if you're going for that kind of sandstone on the top it won't go with the terracotta tiles you have already Do like the pool and tiles that Hayda Natural Stone have posted Very nice!

Hahaha, I'll be happy to do that, but I think it'll be a long wait. I'm kind of an odd one when it comes to doing stuff. I like to think things through, plan and plan again and again, and I'm trying to use as much discarded material as I possibly can. In other words, I'm trying to keep the cost as low as possible. I see so much stuff which can still be used end up at the tip, it's shameful. For the aquaponics system, I will try and replicate the ecosystem that exists in nature (safe for the air-lift pump to circulate the water). Some ways to go on how to do that on a flat piece of limited land. Like I said, lots of plans, but tough to get all the required materials. Thanks for the interest.

horizontal anything is a no, the gap would have to be so small it might as well be solid. yes the vertical cable might pass but you are not allowed to be able to squeeze them together as then the gap distance is non complying, The safest one is the solid section PCA pool fence, or glass, or solid, to 1200 mm in Queensland, no greater than 100 mm off ground, and gaps not able to be manipulated, and to stop that you have to have horizontal section in the cable type, which then do not comply, cut metal screens if complying is OK. I would question the void, and if you know the reason for the void, than solutions will be able to be worked out, now we are asking why? Pools in adjoining yards are acceptable with pool fencing complying on both sides, no void is required. so the void sound a bit iffy, unless it is something to do with storm water, or a building requirement, so ask the question why. Pool fencing can be awesome.