45min should be no problem as long as they use O2. If not make sure it is a very large bag to bring the fish home in. And someone made a good point, climate control em, a cooler (not cooled) would be ideal if your in a high temp area. You can also hit them up to see if the have insulated boxes that you could have to transport. I get them from work from blood samples and it keeps the animals temp amazingly stable.