<span class="link_user">@JolliGrowz27</span>, That is possible. Coco coir plugs can't hold too much moisture like pete pellets can. Its a good practice to let any plug absorb water fully, then squeeze it a little so 5 or 6 drops come out. Then its right. The only way to get root rot after that is overwatering. For germination keep it kind of moist-dry, but moist air, humidity or spraying with atomized water is needed. Adding a fertilizer is useless because there are no established roots yet. It drinks from the cotyledons and uses energy from endosperm at first, then will use stored energy in the cotyledons to power out the first set of real leaves. At that point it has established roots and will be exploring for food and water. I think the rapid rooter would be a food invitation for some things that would also like to eat young sprouts. Save that root fertilizer for once they establish some roots and have plant strength.
<span class="link_user">@The_Wanderer</span>, I've been losing a few using Rapid Rooter. Gonna switch back to soil and solo cups. I think the plugs retain too much moisture, causing the tap roots to rot away. Saving the plugs for cloning only now.
<span class="link_user">@JolliGrowz27</span>, maybe they got damaged when being put into the plugs? Could be possible right? I just let the seeds go through imbibition until they sink, then put them straight into the plug and let them open up there. But yeah germinating is always a tense time. Thanks for adding that note.