<![CDATA[ABSTRACTAquatic plants are important part of aquatic ecosystem that can be used as an phytoremidiation agent, trapping organic matter in eutrophic waters as well as cleaning and controlling heavy metal pollution, pesticides and oil. The aim of research to assess the ability of some aquatic plants to organic matter and phosphate reduction for improve water quality. Research conducted at the Greenhouse of Institution Research for Fishes Resources Rehabilitation in May 2016. The study using factorial completely randomized and all treatment were conducted in triplicate. Aquatic plants are used Azolla sp., Spirodela sp., Duckweed (Lemna sp.), Salvinia sp., Water lettuce (Pistia sp), and water hyacinth (Eicchornia crassipes). Water media used are high stock solution of organic matter derived from fish farming waste water containing undigested, food, faeces and urine of fish. Water sampling was conducted on day 0 (T0), 2nd (T2), 5th (T5) and 9th (T9) after planting. The results showed that the total organic matter) and P-PO4 significantly different based on day of sampling, while the aquatic plant treatment significantly different at P-PO4 concentration, but not significantly different from the organic matter. However, based on the percentage change showed that the wood lettuce (Pistia sp) capable of lowering the BOT and P-PO4 as much as 55.52% and 60.62%, and the water hyacinth can lower both BOT and P-PO4 as much as 23.38 % and 92.68%. Relative growth rate (RGR) was higher in the aquatic plants that tend to be small as Spirodela sp,  Lemna sp and with doubling time (DT) is relatively short. Water hyacinth plants tend to have a lower RGR values and DT are relatively long. The value of RGR and DT related to the availability of nutrients.Keywords: Aquatic Plants, Water Quality, Relative Growth Rate (RGR), Doubling Time (DT)ABSTRAKTumbuhan air merupakan bagian penting dari ekosistem perairan yang dimanfaatkan sebagai agen fitoremediasi, perangkap bahan organik di perairan eutrofik serta membersihkan dan mengontrol pencemaran logam berat, pestisida dan minyak. Tujuan penelitian untuk mengkaji kemampuan beberapa tumbuhan air dalam mengurangi pencemaran bahan organik dan fosfat dalam upaya memperbaiki kualitas perairan. Penelitian dilakukan di laboratorium rumah kaca Balai Riset Pemulihan Sumberdaya Ikan pada bulan Mei 2016. Penelitian menggunakan Rancangan Acak Lengkap Faktorial dengan tiga ulangan. Tumbuhan air yang digunakan Azolla sp., Spirodela sp., Mata lele (Lemna sp.), Kiambang (Salvinia sp.), Kayu apu (Pistia sp.), dan Eceng Gondok (Eicchornia  crassipes). Media air yang digunakan adalah larutan stok tinggi bahan organik berasal dari air limbah budidaya ikan yang mengandung sisa pakan yang tidak tercerna, feses dan urin ikan. Pengambilan sampel air dilakukan pada 0 hari (T0), 2 hari (T2), 5 hari (T5) dan 9 hari (T9) setelah penanaman. Hasil penelitian menunjukkan bahwa bahan organik total (BOT) dan P-PO4 berbeda nyata pada perlakuan hari, sementara perlakuan jenis tumbuhan air berbeda nyata pada konsentrasi P-PO4 namun tidak berbeda nyata pada BOT. Persentase perubahan menunjukkan bahwa kayu apu mampu menurunkan BOT dan P-PO4 sebesar 55,52% dan 60,62% serta eceng gondok mampu menurunkan BOT dan P-PO4 sebesar 23,38% dan 92,68%. Nilai relative growth rate (RGR) lebih tinggi pada tanaman air yang cenderung kecil seperti Lemna sp dan Spirodela sp dengan doubling time (DT) yang relatif pendek. Tanaman eceng gondok cenderung mempunyai nilai RGR rendah dan DT yang relatif lama. Besarnya nilai RGR dan DT berkaitan dengan ketersediaan nutrisi.Kata kunci: Tumbuhan Air, Kualitas Air, Relative Growth Rate (RGR), Doubling Time (DT)]]>
