You can start a cycle (and indeed do a cycle) without a heater, but it will be much slower.
Are you going to be doing a proper fishless cycle, with ammonia? If you are, it will take more than a couple of weeks, I'm afraid.
Your only other option is a fish-in cycle, which will be a lot of hard work for you and dangerous, or even lethal, to your fish (that's why we always recommend fishless cycles on this forum).
Are you going to be doing a proper fishless cycle, with ammonia? If you are, it will take more than a couple of weeks, I'm afraid.
Your only other option is a fish-in cycle, which will be a lot of hard work for you and dangerous, or even lethal, to your fish (that's why we always recommend fishless cycles on this forum).