Buoyancy

Detritus Mulm

Guru Class Expert
Jun 12, 2005
147
0
16
I'm redoing the office tank, so I bought some Riccia by mail order and got some Java Moss as a freebie. :) I'd been soaking them both in some Alum for a few days to make sure I did not get any unwanted visitors. They were both floating in their quarantine bucket, but when I put them in the tank after rinsing, the Riccia sunk to the bottom and the Java Moss floated to the top. The Riccia seems to be making an attempt to rise up, but is still sitting on the bottom.

So did the Alum change the buoyancy of the plants or is it related to some other factor like PH or CO2?
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
Riccia should float; that's how it's found in nature. You've come across an interesting coincidence thought :D

Check this out:
Alum - Wikipedia, the free encyclopedia

Then go look at the back of any water clarifier, and tell me what you see.

Yes, you've changed the buoyancy of riccia with a chemical flocculant.

Why the java moss went up is beyond me.

-Philosophos
 

Detritus Mulm

Guru Class Expert
Jun 12, 2005
147
0
16
Philosophos;41882 said:
Riccia should float; that's how it's found in nature.

Yes, you've changed the buoyancy of riccia with a chemical flocculant.

Why the java moss went up is beyond me.

-Philosophos

I guess there was more 'crap' in the Riccia weighing it down, but it did not sink when it was in the Alum. It's slowly making it's way up now.
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
When it was in the alum it would've had a lower density than the solution, where as in your tank the solution density would've been lower causing it to sink. That it's rising now may mean a tendency to bond to other particles besides the plant. Let me know if your water looks any clearer by tonight or tomorrow ;)

-Philosophos
 

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
1
36
Surprise, AZ
Hi,

For what it is worth, I suspect the alum level was a bit high or left in the solution for a little too long.

I doubt it did any harm.;)

I have seen the floating Java Moss, I don’t really know why, just every now and then they get that get up and go kind of attitude.:)

Biollante
 

Detritus Mulm

Guru Class Expert
Jun 12, 2005
147
0
16
The Riccia is back on top. It sat at mid tank most of the day, but I was doing some work in the tank and it got bumped to the top and is now staying there.