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New tank idea


O. vulgaris
Apr 27, 2007
I've been thinking about building my own tank. I'm considering a tank 8 foot long x 4 foot wide x 30 inches deep.

I'm going to divide the tank into three sections; two 2 foot x 4 foot sections - one on each end, and a 4 foot by 4 foot section in the middle. Each section would be sectioned off so water could flow between the sections but everything else is kept seperate. In one small section, I would like to keep my octopus. The middle section would be my reef tank, and the other small section is kept for other fish that aren't reef safe.

I'm going to build the tank out of plywood. I have been researching on line to get all the details on fiberglassing and sealing the tank. The only glass will be the front panel.

With a tank this big, the capicity will be somewhere around 600 gallons.

While I have read a lot about building tanks this big, I have not read anything on dividing the tank in the manner I have described. Does anyone see a problem with this idea? I thought I would run it by everyone and see if anyone has any thoughts I haven't come up with yet.

Remember that this behemoth will weigh three tons when filled--I suspect your floor would have to be reinforced. I think you'd be better off buying a few decent sized tanks, then you could distribute them in different rooms in the house. Another reason to do this is the specific needs of each animal: if you want to keep a bimac, it won't live very long at the tropical reef temperature. If you're keeping a FO section it will certainly be generating more nitrate than the reef would like, etc.

i would think you would do better to give each section its own overflow with its own return line.. and just have small holes or slits in the dividers for micro life to pass through..
I live on a concret slab so the floor is no problem. I have thought about the nitrate problem, but if I don't overstock the reef tank, in fact, I plan to understock it, the live rock, live sand and 600 gallons of water should help equalize it.

These are just my thoughts. Tell me if I'm wrong.

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