Planting crypts, floaters with a HOB.

maybe something that would leach dye, like yarn? I've used black sewing thread to no harm
 
maybe something that would leach dye, like yarn? I've used black sewing thread to no harm

That's what I meant, I didn't know if the string might have some coloring or chemical in it that might be a little dangerous.
 
I think you'll be fine with most string, just avoid waxy string. I also don't like the way things seem to work out with fishing line. It's a fine material, but it never breaks down and I always end up wishing I used thread.

As far as the fern debate, My java ferns do ok planted in the substrate, but I notice faster growth when the roots are free to feed off the watercolumn. I like how it encourages them to grow so much root mass. I like to tie them to wood in places where the roots can drape over and around, and eventually reach the substrate. But this makes moving them harder.

Putting the floaters outside or in the window ought to be fine, although insects love to eat floating plants. Smaller stuff like duckweed will grow insanely quick in sun. Personally, I like the cover floaters give my smaller fish, but I don't keep them in all my tanks, because they take over fairly quickly. The red root floaters seem to be the slowest growers I have had, and don't like being disturbed much... but with some bright light and time, the roots come to look really nice. They need very little to go on once they're a full size plant... I gave some to my GF months ago, which she keeps in a glass bowl on the windowsill, watered with tap water. It looks as nice as the nicest in my tank, and the bowl doesn't have a spec of algae.
 
good info so far. i'd just like to add rubber bands to the list. they can make attaching java ferns a done deal.

for your floaters having a larger plant that will reach the surface in front of your filter will keep them out.
 
I made a fence for my floaters out of plastic craft canvas and 2 suction cups. Made it about 1.5inches wide and it holds them nicely. It's clear, so it's not really that noticable.
 
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