How fast does Java Moss Grow?

[FrozenFins]

I was wondering, how fast does Java Moss grow when floating? Under the right conditions can it be consiered a weed?

Edited March 17, 2021 by JamesB

[Kirsten]

I'm afraid I don't have any specific answers, but I've always grown mine free-floating and it's always just been sort of...hanging around, green, tangly, near the bottom, occasionally sticking to rocks but mostly trying to strangle java fern roots. Great hiding place for fry, but not noticeably growing out of control or dying back.

[gardenman]

Under the right conditions just about anything can be considered a weed. I don't find java moss to be overly annoying though. (At least compared to duckweed.) Maybe once every three months I'll go through and remove a bowl of java moss from my four tanks. I take out a big bowl of duckweed and assorted floaters every Saturday. Java moss is growing most robustly in my ten gallon quarantine tank right now (even pearling pretty briskly) and will get thinned out in a few days as I've got some red ludwigia coming that will end up in there. I had a big raft of it growing in my thirty high on the filter spray bar that I removed a while back and it hasn't regrown much. It won't stay floating in a tank. It'll either settle to the bottom or hang up on something like a spray bar, heater, filter tube, etc. and grow from there. I don't find it a problem. I've heard people saying it's impossible to get rid of and you should never put it in your tank, but it's not really a problem for me. At least so far.

[Patrick_G]

It doesn’t seem to grow very fast in my tanks, at least not fast enough to be a nuisance. I’d actually like it to grow a little faster!