Pearling brown algae

[funatnight]

I just added a DIY CO2 to my 75g tank yesterday.
I have a few questions:

1. Some of the stalky plants have long white hairs growing out of them towards the bottom. I assume that these plants are trying to develop new roots. This is a good thing correct?

2. I have some brown algae on my rocks and now that I have added CO2, there is little bubbles all over it. :help: Any ideas?

 

[Blinky]

Most stem plants will sprout these roots. If you were to bend the stem down and plant the roots in the substrate, chances are the plant would sprout a new stem from each leaf node. When I had Ambulia sessifloria, it used to crawl along the gravel, putting out roots at each node and growing new branches upwards from the original horizontal stem - it spread very quickly this way.
I've never seen algae pearl, but I don't doubt it's possible. Otos like diatoms (brown algae) a lot, if you want to get rid of it I'd suggest getting a few (if they're compatible with the other tank inhabitants).

 

[funatnight]

The algae was just sitting there not doing anything until I added the CO2, and then it started to pearl (which I assume is the plant's way of giving off oxygen).

Do you have any suggestions for keeping the stem under the gravel? I have several plants that have started to do this, and it seems like the roots are about 1/2 way up the stem. Should I cut the stem and plant it, or should I leave it attached and just bury a portion of it?

 

[Blinky]

If you want the stem to branch out, you can do either. Leaving it in the gravel and weighing it down will probably result in this happening faster - placing a cutting horizontally on the gravel may take longer as it will need to acclimate for a few days before it starts growing, as with any cutting. You can bury the roots in the gravel if they're long enough, I have weighed stems with short/no roots down (gently) with pebbles before and allowed them to grow roots down into the gravel, they take hold fairly quickly.

 

[funatnight]

What are your thoughts on the lead weights that come on new plants? I was sort of leery to put them in my tank, but the LFS guy said that it was fine. Should I try to buy these weights?