hydrocotyle tripartita decorative aquarium plant with hydra viridissima also called green hydra freshwater polyps in the aquascapi

algea also aquarium aquascapi aquascaping aquatic asexual biological biology botany called chlorohydra closeup cnidaria decorative engraved environmental etching fauna flora freshwater gentle green hydra hydrocotyle hydroida life micro microbiological microbiology natural nature organic organisms overgrown photographs plant plants polyp polyps symbiotic tripartita underwater viridis viridissima water wildlife