If I hatch turkeys in my older model hovabator with fan they actually hit their heads on the fan. I would assume they are also hitting their heads on the element because it is lower than the fan, they dont seem to be harmed. I personally have never used any other method to add humidity in my hovabators except the trays in the bottom. but if one uses air conditioning in the summer and furnace heat in the winter, especially in certain climates and with a forced air model, there may be times when added humidity sponges may be nessesary. I have a few of the old square models, that did not come with the plastic liner, then they added the plastic liner, then they came with the yellow strips to secure the wire mesh to the plastic, then they switched to little wire clips to hold them together, along with that came the higher dome models. And the flat bottom styro with more reservoirs in the newly designed plastic tray. Obviously they are aware of the flaws and problems and are taking steps to improve.