Is this enough cardio? Do you have a plan that you stick to? I plan to hire a trainer after I have lost weight to tone up but I need to loose 50lbs first. I am tracking what I eat and will hit the gym at least 5 days a week but I need a plan to stick to.
To stick to something you need to find something you are going to like. Are you going to like sticking to the treadmill and elliptical for weeks on end or is there something else you would want to throw into the mix? Class at the gym? Swimming? Biking? Weight lifting? Etc?
Personally, I would find it very hard to stick to elliptical and treadmill workouts only, but if you like it, do it!
What does your current cardio routine look like? If you go from zero to an hour five days a week there is a significant chance that you will get hurt. I'd ease into the working out and try and create a workout that you can stick with.
Personally, I can't do the same workout everyday. I need a little variety or I get bored. Strength training is a good addition to any program and I'd think about hiring a trainer long before you drop those 50 lbs.
Do you have classes available to take like swim aerobics or zumba? Also, yoga would be a nice addition.
I'd also switch it up with the stairclimber, rower, some cycling, and the elliptical. A good variety will help you use different muscles and keep you from getting bored.
I also encourage you to get a trainer to show you how to correctly use the weight machines and to get a weight program started. Trainers are there to get you started safely and help you with your goal regardless of what is it. I highly encourage you to add strength to your routine. It is just as important in achieving your goals as cardio!