Plant ID?

These plants were floating down the Smith River in North Carolina right before it meets the Dan River. I scooped some up and took them home with me. They look like potamogeton crispus to me, but does anyone who knows more about plant species have an opinion?

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You can click on the images to make them bigger.

I put some in my 80 degree Fahrenheit guppy tank and some in my 70 degree F Elassoma gilberti tank. The DH of my tanks is zero. I hope it'll do okay in the 80 F, 0 DH tank but the people online say that's at the upper limit of P. crispus's tolerances, so I'll keep an eye on it and see if it starts melting. If I have ID'd the species incorrectly then who knows what its temperature tolerances are.

Edited by EricaWieser, 27 August 2012 - 07:43 AM.

You got it. About 4 years ago I scooped some up like you did. There was a bunch of Vallis floating by and I ended up scooping up some of this too. I never kept it long term, and never had much luck. I just kept it floating in the tank for a while until I saw roots, and then plated it. But the stem ended up melting away.. Sorry I don't have any pointers...

Looks like P. crispus to me. I have seen it in isolated patches in many rivers here in VA. A few years back I was fishing in the Brandywine River in PA and it was choking entire pools in some places. I had it growing in my 75 gallon, but beware that it does not behave. It produced turions that rafted to every corner of the tank, and then sprouted. If it would have grown nice and dense I would've kept it, but it was leggy and invaded the tank. Of course I have strong current and had a chiller on the tank at the time, so that may have contributed. But just be aware of its invasive capabilities...

I'm pretty sure that's crispus, but if you want to make sure, look closely at the leaf edges: crispus has serrated ones on mature plants. It hitchhiked on another plant I brought home once and it grew like a weed; it's a bit annoying really. I didn't really have as much of a problem with it breaking into bits as say, slender niad, but as Kanus said, it grows fast and leggy and is hard to tame. Make sure to dry it out and burn it or at toss it in the trash if you don't want it so it doesn't invade a new waterbody.

Edited by Orangespotted, 27 August 2012 - 02:54 PM.

Update: The plant is now touching the surface of the water. I think it likes it in there.