You can float ice inside of bags to help lower the temp or coke cans just float it at the top right under the lid you will have to switch the can every 30 min or so due to it not being as cold. When it got hot here where we live that’s what we did and it helped a lot ultimately you can do a water change too in an emergency if it’s super hot but don’t drop the temp too fast on them to not shock them. Other than that that GirlTalksFish video is your best bet too, she works with aquarium coop and would know the best thing to do!
hope that helps a little