Hi @CEH , hi @EricL . Windy balconies can be tricky, and your Ctenanthe and peace lily are not well suited to that sort of environment. They're better off indoors, or in a shady, humid area.
Both plants lose a lot of water via evaporation from their big leaves, and wind will make them dry out even faster - just like it dries out laundry on the line.
The leaves on the Ctenanthe and the peace lily will develop crispy brown tips if they dry out for too long. That won't kill them, but they won't look anywhere as nice.
Could you maybe keep the Ctenanthe in the bathroom? It will appreciate the humidity and it will be easy for you to take it in the shower with you to give it a good drench every week or so.
BTW, Seasol is a tonic, rather than a true fertiliser. When you repot a plant it's nice to give it a hit of Seasol diluted in the watering can to stimulate root growth. For fertiliser, as Eric said, the Osmocote slow-release is a good one.
Just looking more closely at your pics, have you left your plants in their little black plastic pots and then half-buried the little pots in the bigger pots? The best thing to do is take the plants out of their little plastic pots and plant them directly into the potting mix in the bigger pots.
For a windy balcony you can always consider bushy succulents like the Jade plant (Crassula ovata) . They don't have that leafy look but they're low-maintenance and tough as nails.
Hope that helps!
Brad
