Wow! I take it you guys like the Marsilea species, so I'll answer that question first. It was sold to me as Marsilea quadrifolia, but I actually believe it is Marsilea hirsuta. I got it at PetSupermarket, a big chain petstore, for like $3.99 for a small pot. The plants have been underwater for over 10 months, so they are not new. The four-leafed and single-leafed shapes are what grows in my tank. Mostly the shorter four-leafed. The emergent growth was a lighter green, taller, and had a thinner texture. The leaves I have now are thicker and a darker green. My tank had 1.4WPG. It now runs on 2.1WPG, but that's recent and only because my bulbs are old and no longer producing as much light, so I had to compensate until new bulbs can be ordered. Supposedly this plant changes leaf shape based on the conditions it's being grown in. This tidbit is according to the Tropica website. I add nothing special (Nutrafin CO2, no ferts except fish poop and a rootab when I remember). It spreads everywhere.
Now for the camera question. It is an older model, and I got it pretty cheap at Amazon. A Canon Powershot A430 with 4.0 megapixel, 4x optical zoom, and a super macro-mode, which is the mode I used for the shots above.
Finally for the Blue tetra question. My blue tetras are less than 2 inches, more like 1.50-1.75" long. They are a nice fish, I wish I had more of them. They move almost like danios and the coloration is very subtle. I've only seen them on occasion in LFS in the states. They may be more common on your side of the pond, Dave.
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