"Should be fine"... hmm OK.
However, safe aquatic plants for your turtle include:
Aquatic Mint Mentha aquatica
Cabomba Cabomba caroliniana
Cumbungi Typha latifolia
Duckweed Lemna spp
Dwarf Ambulia Limnophila sessiliflora
Eel grass or Ribbon weed/Ribbon grass) Vallisneria
Fairy Moss Azolla spp
Floating Fern Salvinia spp.
Foxtail/Hornwort Ceratophyllum demersum
Frogbit Hydrocharis morsus-ranae
Hornwort/Foxtail Ceratophyllum demersum
Hydrilla Hydrilla verticillata
Lotus Nelumbo
Tropical and Hardy Waterlilies Nymphaea spp.
Water Caltrop Trapa spp.
Water Chestnut Trapa natans
Watercress Nasturtium officinale
Water Hyacinth Eichhornia crassipes
Water Lettuce Pistia stratiotes
Water Meal Wolffia arhiza
Water Milfoil Myriophyllum
Water Plantain Alisma plantago aquatica
Water Ribbons Triglochin procerum
Water Snowflake Nymphoides indica
Water weed/Pond weed Elodea spp.
Here's a list of safe Terrestrial plants for around the pond:
Australian Native Violet Viola hederacea
Cyprus grass/Papyrus sedge/Paper reed Cyperus papyrus
Dianella/Flax lily Dianella spp. Turtles will eat the berries that fall from this plant/safe for humans too
Lilli Pilli/Brush Cherries Syzigium spp. Many species produce edible fruit known as roseapple
Lomandra Lomandra spp.
Midgen Berry/Midyim Austromyrtus dulcis Turtles will eat the berries that fall from this plant/safe for humans too
Pandanus/Marita
Swamp Banksia
Swamp Bottlebrush
You'll also want to cover all those rocks with soil mixed with river sand.
[doublepost=1526114679,1526113472][/doublepost]These Aquaculture ponds make the best turtle ponds mate and they're really affordable. I'm busy building a new 10,000 litre one now.
http://www.blueheelertanks.com.au/aquaculture-poly-tanks
Here's AFT's 10,000 litre Macleay River turtle breeding pond.
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