Plant Problems

Hi all.  I've recently converted from the group to this list, so this is 
my first post here.

I have a few questions.  First off, my 29 gal tank has been having some 
problems recently.  I've noticed small but increasing amounts of green 
spot algae and a hairlike algae.  Also, my water wisteria has been losing 
little bits of leaves, and holes are appearing in some of my other 
plants.  I add the tetra iron stuff every water change because that's all 
my budget will allow.  The affected plants are some of my oldest, so I 
don't think its just that they're running out of stored nutrients.  
However I could be wrong.  I already checked the FAQ on this and it 
wasn't any help.  Lighting is two 20 watt FL, and pH is about 6.5.  The 
fish load is fairly light.  Oh, and the water turns yellow too, although 
this may be from the driftwood.  Any suggestions on how to get rid of any 
or all of these problems?

Also, someone mentioned sandblasting gravel as a substrate.  Where does 
one acquire this stuff?  Hardware stores just give me a blank look when I 
ask.  Same thing with laterite, vermiculite, etc.  Fish stores have never 
heard of any of it (I gotta try some better stores! =)).  While I'm 
looking for stuff, a source for SAEs and trumpet snails in the Seattle 
area would be greatly appreciated.

I'm building a heated-water-pump PVC-pipe substrate-heater-widget for a 
larger tank like they had in AFM a while ago.  Has anyone out there tried 
this?  Does it work?

Thanks for any and all replies!

- Nick Livingston            Today's Words of Wisdom:
"Sometimes I wake up grouchy, sometimes I let her sleep."