I have been following this thread for a while and I must say that you should charge admission....not only to view the aquarium but also to feed the Koi! Beautifully done and well thought out.I had to separate arowana from gar to my second aquarium, because arowana beat gar a lot.
Year 2011 I started to build aquarium from reinforcement waterproof concrete. Dimensions are 600x170 cm and there is 100 cm water level. Tank volume is 9600 litres (2500 gallons). Front glass panel has 3,8 cm thickness with weight 580 kilos.
more pictures you will find here: http://www.numa.sk/en/our-offer/detail/mega-tank
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