DeeBub is right, no matter whether he states it in a rude way or not.

The fact is that if you wish to be safe, and not risk the death of your frog, then you must remove the gravel. Impaction is a major threat to frogs kept in unsafe environments or fed unsafe foods, and has caused the deaths of many loved pets. Please, do not let that happen to your frog.

And I agree, cleaning gravel can be a real pain.