Sounds like your humidity is too low...the veins you could see - were they big fat ones or little bitty spider looking ones? As just for reference, humidity is not raised or lowered according to how deep the water level is but by how large an area of open water you have. So it can be super shallow bu if it covers a large area your humidty will be higher than something that is real deep but has a small area of surface water....did that make sense?