Actual Mekong Giants
Mekong giant catfish (Pangasianodon gigas) grows to 3m and 350kg. Arapaima (Arapaima gigas — not native but similar) 2.5m. Giant freshwater stingray reaches 2m disc.
These fish need truly massive enclosures — commercial aquaculture ponds or public aquariums only.
Don't Buy Baby Giants
Pet stores sometimes sell juvenile Mekong catfish, iridescent sharks, or pacu. These grow rapidly.
Unethical purchase — 90%+ die in home tanks within 2-3 years, severely stunted and stressed.
Aquarium Alternatives
Smaller Pangasius species (short-bodied pangasius) stay under 30cm with proper care. Thorax catfish (Wallago leerii) tops at 40cm.
Native loaches, barbs, and rasboras replicate Mekong feel without size problems.
Public Aquarium Visits
Phnom Penh Aquarium, Tonle Sap Research Centers host actual Mekong giants for public viewing.
Support these facilities rather than keeping giants at home.