A 20long for my main 225 display, which lasts 5 days. I have it on a solenoid controlled top off connected to my main 55 g rodi storage, with safeguards n apex . It’s tucked away under the sump so refillingnit by hand would be a challenge. This automates it- and means I literally have never opened the lid or moved it in the 3 years it was in use before I moved house. It was pristine inside. Use a hydrofil ato system
a 10g for my 20long coral qt and another for my 50 lowboy frag. Uses a knock of autoaqua smart ato
my 10g temp tanks have a 4.75g square plastic storage container from Target that cost like $3.88. I have 2 more that I use to culture pods in, that I added plastic spigots to. Float switch and relay set ups, diy
I’ve also used 1 gallon cheese puff containers and square plastic 0.75 gallon rice containers for my smaller tanks with lids that only go through a gallon every 6-7 days