snail issue; control. And plt ID      11/20/13
Hi Neale, hope you are well.  My tanks are doing well, so I haven't needed advice lately.
<Well done!>
Here is a photo of a plant I'd asked about before.  Someone told me it's probably called naja grass.  What do you think, have you ever seen it?
<Certainly looks like Najas guadalupensis. But no, I've not seen or kept it. Seems to be rarely traded here.>
It has long stringy roots but doesn't succeed in being planted for me at least in the lower light setting.
<Correct. It looks much like other aquarium "tangle weeds" such as Ceratophyllum demersum and Elodea spp. Basically, it wants to be left loose, floating under bright light, and it will send down white roots to form loose anchors onto the sediment. It'll grow from the waterline downwards rather than from the substrate upwards.>
It tends to have explosive growth like the java ferns if it is growing tangled among other floating plants.
<Precisely.>
The one I'm referring to in this picture is in the center and not the annubias or the water wisteria/water sprite(i have both or one of those). 
It's lacy and the roots are floating too.
Here is my real question though:
In your experience, do assasin snails ever get each other ever? 
<Possibly, but this seems rare.>
I originally had 5.  Some time back I found one smaller empty shell.
<Yes.>
Lately I had only ever been aware of 3, though it's possible one is hiding.
 But today I noticed another empty shell, this was one of the larger ones.... It's been there unmoved upside down since yesterday. I had hoped these critters would eventually breed and not cannibalize.  I have heard stories that they do reproduce, but I have seen no evidence of this.
<Ah, they do breed. But they're also unusual in not being hermaphrodites.
So if you (unluckily) got few/no females, then your population would die out.>
Would they ever react badly to a water change, are they sensitive or hardy?
<They seem fairly hardy.>
It's heavily planted.  This time I cleaned it a little more thoroughly in the vacuuming, I changed a little more water than typically (45% maybe as opposed to 25-30%, and my tank has a larger than needed filter for currents), but there's also lots of decor and plants and a well established filter, and the snails were removed and kept in their water during the cleaning.  The fish have shown no signs of stress.  They even gave birth since the cleaning.  The endless lime green endlers....
<Cool!>
Do the assasin snails eat baby cherry shrimp?
<Some reports suggest they can, but it probably depends on many factors including whether the baby shrimp had places the snails couldn't go, like behind/inside filters, and how many of each you started off with.>
That tank could use some resident snail cleanup, but I would hate to stick one in there and have him feasting on shrimp instead.  I'm wondering if there's anything that could coexist with them and do snail patrol that wouldn't eat them too.... Probably not.
<I wouldn't keep Assassin Snails with my *only* group of Cherry Shrimps, but I have combined them in one aquarium while keeping another population of Cherry Shrimps going without Assassin Snails in another tank.>
The funny thing...I have never seen one eating a snail, even with baby snails in the near vacinity.  One in particular has been very active since the clean.  I wonder if he was the culptet in the other's demise....
<Oh, Assassin Snails can/do eat snails, but they're scavengers more than anything else, so if there is other food, they'll eat that as
well/instead.>
Thank you,
Jill
<Most welcome, Neale.>