Beginner Gardening: Spider Plants (4) new plant owner questions, 1 by tikipod

tikipod wrote:
I recently bought 3 spider plants and have been raising one baby my neighbor gave me. The new ones have all been bought this week since I've been caring for the baby so well but I ended up with some questions as result.

I have a fairly large all green spider that had two spiderling/flower stems and appears to be 5 spider plants stuffed into one 6 inch pot. Since the roots were sticking out the bottom I repotted it in an 8 inch pot and prior to repotting the soil seemed to be similar to a seed starting mix. I also notice some leaves are dead, but nothing too worrying.

The second is the type with the white edge and the green center. There are two plants and they were in a 4 inch pot. I transplanted them into a 6 since their pot was broken from roots exiting the bottom.

The third is a Variegated Bonnie, very very curly and has about 17 babies. The tag said 6.6 but only the "rim" was 6.6, it appeared smaller on the bottom. The plant was sticking 1/2" and 1" above the rim of pot and the soil was completely dry. I don't think it received proper watering. Some of the leaves are also turning brown in the center, not just at the tips.
When I removed the drainage to check if the roots were coming out, which they were, the saucer was filled with some dried/crusty stuff. I transplanted it into a 7 inch pot.


So my questions are:
Does anyone know what the crusty stuff might have been?
Since several are in one pot and they are entangled, can I safely divide them and if so would I just simply cut them?

Also a gal at the store gave me some advice:
She said to use filter or distilled water but would using water from my pet fountain be ok?
She suggested I transplant new spider plants with "Nothing but new soil, none of the old", so should I rinse the old soil off the roots?

Added a photo of my newest, will add others if you'd like.