I have noticed some air bubbles in my bottom pond this week where I have the largest Koi! In the top pond it is covered with plants and I would like to take the smaller koi out and put them in the larger pond below for the winter since it is covered with a heavy wood lattice! Any idea's for me other than removing the plants and take the koi out then putting the plants back? Photo shows top pond with plants and the bottom pond is covered with the lattice with the waterfall between! Thanks, Jacque