Do I need to fridge my axies?

We're having something of a heatwave here in the UK and I'm struggling to keep the temperature down on my 2 tanks. The fridge is full of chilled water which is being added 2-3 times a day and I have aquarium fans on full blast. I'm struggling to get the temp below 21℃.
My 600l tropical aquarium is at 30℃ without the heater or any lights on, so my efforts to lower the temp in the axie tanks is definitely helping!

The axies are behaving as normal but I was wondering if they'd be more comfortable if I were to pop them in the fridge for a couple of days?

Any advice would be gratefully received - I just want to do what's best for them!

Many thanks,
Karen

Fridging them is usually only for illness reasons. Unless your fridge is set 50+ degrees F, it'll slow down their metabolism a lot. Putting them in there for a few days will cool them, but returning them to the tank just puts them back in a high temperature.
Options I know of:
-Fans on the tank: Have them on both ends of the tank blowing the same direction so it moves air across it and keeps any hot air from settling on the tank
-Frozen water bottles: I've only read about using this on larger tanks, so I assume if your tanks are larger than 20 gallons, you could try frozen water bottles
-Wet towels: Surround the tank in damp towels and aim fans on the towels to cool it
-Use more water: The more water there is, the longer it takes to heat up and the easier to keep cool it is! If your tanks aren't filled all the way, fill them up more.
-Make your own franken-chiller: Just look up how to make an aquarium chiller on Google, you can choose whatever option you feel most comfortable with.
Hopefully this helped! Good luck