Effervescent tablets. Vitamin B+ Performance Orange also available for the same price:
https://www.woolworths.com.au/shop/productdetails/814718/voo…
I used these at the gym as a substitute to Hydralite and Gatorade as I am quite often dehydrated, it helps fight that sudden loss of energy that I sometimes get. Note, these have quite a sharp / acidy taste so if youre sensitive to that, hydralite might suit you better.
Some of these are $5.40 @Amazon with subscribe and save option if you were looking for other Voost products. Voost Hydrate Lemon + Lime Effervescent Tablets 20 Pack
Voost Performance Vitamin B+ Apple + Berry Effervescent Tablets 20 Pack $3.96