New water = Cobweb?

[blacktarotannis]

I'm sure someone will come up with the answer.... Does it bother your fish? Maybe pull some out take it to a fish store? Whats the temp of the water? Oh maybe try adding the water in a diff. way.... *shrug* Give everything a good scrub and then see if it happens again?

 

[hovmoller]

I'm guessing that it's either some sort of algae or some form of bacteria. I get something similar if i go a long time without a water change in my planted tank. Generally i find though that if i put a plate in my tank and empty the water slowly over the plate it doesn't stir up the stuff. Not sure what it is but i'm sure that someone will know.

My tank is also well planted with clay type substrate under the gravel.. Do you mean that you get something similar when you do a water change after a long time?

I'm suspecting it's because of clay "dust" getting stirred up when I add the new water but why it "coagulates" and sticks to everything is what I don't understand.