Originally Posted by taboule

This reminds me to share my experience, that good technique has at least as much to do with successful and productive germination (and subsequent seedling health) as the equipment itself. I've only used the most basic heating pads (mostly ones that come packaged with a 10x20 tray and pucks) and alter the technique to match the plant variety and batch size.

Even when germinating all seeds of-one-kind in a flat, many days separate the first ones from the laggards. As Loulac mentions, the dormant seeds and seedlings need different environment, not only moisture, but also different heat and light ideally.

I've settled on using "removable" media, either tiny 2x2 square pots (with one or 2 seeds per) or peat pucks in my germinating trays. I inspect every day for emerging seedlings, and immediately remove them to a cooler shelf under intense lights. I then can replenish the vacant spots with new seeds and media.