Ich that took tank over

So ich pretty much wiped my tank out besides the algae eater i have in there.

Its been in there alone for about 2-3 weeks now after all the other fish died.

Is there anything i should do to the tank before adding more fish? Replace filter or whatnot?

Ive cleaned the gravel out with a cleaner and have done some small water changes, but should everything be cleaned before adding fish or should the problem be gone now

Be careful about getting the gravel too clean. That's where all the good bacteria live. A fairly large water change would not hurt, but also be sure to check water parameters, including temperature, before adding fish. More important, start out with only a few fish, and make sure they are healthy. If the new fish are healthy after about a month, then you can add more fish after you make sure they are compatible with the others and the aquarium capacity. Over feeding and over crowding produce most aquarium problems.

im pretty sure adding mardels coppersafe would be a good idea although a second opinion on what i said she be sought after hope i am right

You really don't need medications if the aquarium water is healthy. If a fish is really sick, medication may help, but they will not deal with the source of the problem.