White algae/fungas? Looming diaster?

[craigster]

Have an outbreak of something I can't identify in freshwater tank: a rapidly growing white growth almost like the work of silk worms! Or a fungas not unlike juvenile mushroom spores, but don't know if such is possible fully submerged?.

For last 2 weeks, is forming a thin carpet on bottom with white nodules e very few mm. "Runners" spread some distance. Light gravel substrate becoming stained dark grey to a much deeper level than the white growth. (see pic) Water smells off, slightly rotten/putrid.

Recent events:
* 8 weeks ago used some cotton wool (a cheap variety which broke up somewhat) around roots of some small plants which I had transplanted in containers. (I suspect this was source of problem as roots gradually rotted badly and plants died. but this is definitely a growth, not cottonwool.) The growth spread from that location in last 2-3 weeks.
* Drop in Ph from 7ish (normal) to 6.6 (last 3 weeks)
* Also, rise in Carbonate hardness from 140ppm to 250ppm same period
* Added new river tree branch from LFSa about 1 week ago after 4 weeks of soaking. Now notice beginnings of white spore" nodules on roots of Anubias Barterie var nana which i was trying to cultivar from mother plant
* Added new plants from LFS nottried before about 2 months ago
* In last 3 months had first ever outbreak of brush algae, treated twice with immersion of plants in 1:19 solution of bleach then rinse in clean water before return to tank, with seeming good effect

Other tank specs:
http://www.aquariacentral.com/forums/showthread.php?t=21265

Have now removed top layer of affected gravel and discarded + thorough vacuum.

Any ideas on what it is and how to treat further spread? Seen similar?

Thanks
Craig, Sydney

[reiverix]

I've not seen anything like it. If it smells bad then it could be some form of slime algae i.e. bacteria. Does it peel off easy or is it stuck fast?

btw that plant in your picture looks a bit like an acorus. If it is then it's not aquatic.

[ergo sum]

Maybe something in here. If so most likely from the wood. Just a guess.

http://www.skepticalaquarist.com/docs/biofilm/molds.shtml

[craigster]

btw that plant in your picture looks a bit like an acorus. If it is then it's not aquatic.

Its at least similar, but from my searching to date I've not seen any reference to a variegated variety of acorus. 6-8 wks so far and no sign of deterioration. Then again, plant id I find quite hard (anyone know the best websites?)

[craigster]

If so most likely from the wood. Just a guess.

Thanks, v interesting link. The problem though, pre-dates the wood as best I remember. I week since the cleanout and no obvious return. Have also added a commercial algae treatment, more to stop the brush algae and slow the green algae on the glass a bit.