Well I got home last night to find my blue marble male dead. :( He and the very pretty girl both has this clear slimey stuff in their bowls. It isn't cottony, their fins look great and none of my other fish have ever had this. What is it?

Could be slime algae.
I would clean the bowl and anything in the bowl really well with hot water and either bleach or vinegar. ^_^

sounds like it to me. Clean like she mentioned but make sure to rinse well. I used to have a 2 gallon container that used to get it. It had a live bamboo plant in there and I always had to wipe it off the leaves. It would get on my marbles too. You might want to cut down on how much light the container gets. Is it near the window where the sun comes in? That could be causing it too

No, it is only is those bowls with those fish and it isn't getting any more sun than any of the other containers. I've seen slime algae but I haven't seen it clear.

Hmmm... I think that I would still clean it out really well. It might just take care of the slime problem ;)

hmmmm your best bet would be a 100% WC and toss in some meds to prevent it in case there was a bad disease. Better to be safe than sorry :(

If it's clear and on the bowl and whatever else is in there other than the fish it may be diatom. It's the same thing that makes rocks in a lake slippery. Usually it's more likely to be an issue in hard water though. Just a long shot here, but when you were doing water changes is it possible that these 2 bowls didn't receive the same conditioning treatments you use for the others? Either that or maybe these 2 got missed accidentally at water change time.
As I'm sure you've noticed, the insides of your bowls normally will get a slippery feel to them. That is normal and nothing to worry about. Actually, beneficial bacterial on the sides of your bowl will help in the breakdown of fish waste. The only reason for cleaning is it's prettier to look at. I always leave an area in all my containers alone. There are zooplankton amongst the bacteria that the fish nibble on as well. In college we would check it out under the microscope. It's amazing all the life in there.
If the heavy clear slime is on your fish, that would indicate either a parasite or water quality issue. If it's just on the surfaces of the stuff in the bowls and not on the fish, something else caused your fish to die.

ok, just to be sure everyone knows my bowls are on a 3 day schedule for cleaning and 100% water changes. I'm on a well so there are no water treatments at all. I've never seen anything like this before which is why I wrote here. ^_^

I wouldn't be concerned about the slimey bowls. It is odd that it coincides with the mysterious death. I went to college for Aquaculture and there wasn't anything harmful that we covered that would be causing the clear slime. If it had direct sunlight and was red, then maybe, but not clear, green or brown. In a 3 day rotation even blue isn't an issue. I also have well water. Kinda nice not having to worry about chlorine and chloramines! Chances are you do have hard water. Although heavy metals do build up in the fatty tissue of fish I'm not so sure it's what killed your male. Unless he was just not as capable of handling it. With inbreeding, who knows. It wouldn't be a bad idea to get an additive to neutralize the metals in your water, unless you have a RO unit, which then it would just be a waste of money. I wish I had an answer for you on the death. From what I've learned I just don't think the slime is connected to the death. The only way that I could see that connection is if that bowl accidentally got skipped. Then it would be because of water quality. If he spooked easily, darted around and that kind of behavior the day before, that would be another indicator his water quality was in trouble. Maybe someone unaware of the water chemistry aspects was feeding him, and maybe that female too, extra. That would also account for the extra thick bacteria on the sides of the bowl.

What about the possibility of the "slime" actually being his slime coat?
A lot of fish, when sick or stressed lose a portion of their slime coat.
Just a thought.
Maybe I missed something though.