I had them in my pond. As long as the water level seemed pretty stable (within a 2 foot variance from Spring to Winter) they seemed to do OK. Once the water started doing it's wild swings (up to 7' low now and it has been at least 5' low for the past 2 years) they died off. I don't know if any seeds will re-sprout once the water levels get back to being close to full pool again.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).