Halophila ovalis plants collected from the native environment (Lat. 04°54.473′N, Long. 115°22.299′E-Pantai Bangat, Lawas, Sarawak, Malaysia) were grown in aquarium culture system to assess: (i) the feasibility of using planting materials e.g. rhizomes with and devoid of leaves, (ii) the growth and development of the plants under non-native substrates, fine beach sand and coarse river sand, (iii) the sustain growth and development of the population, and (iv) the tolerance range of plants under the tested salinity and depth. These assessment were achieved by planting rhizomes with or devoid of leaves in the tested substrates in containers, maintained in artificial seawater of various salinity, with minimum aeration and exposed in shaded outdoor natural condition. The artificial seawater permitted a standardization of the medium. By manipulating the placement of substrates in the container (and planting of rhizomes into individual container) then submerged at different depths into the aquarium facilitated observation, recording of data and transferring of plants from one test condition to another. The morphological changes of the vegetative parts e.g. leaf, petiole dimensions and paired cross-veins numbers of H. ovalis in the created conditions were compared to those of H. ovalis from native environment.Proceedings of 4th JSPS-VAST Joint Seminar on \u27Coastal Marine Science\u27, Hai Phong, Viet Nam, 26-28 October 2009Oceanograph
