Open Loop Estuary Tank

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Snug Harbor

Aquarium Advice Newbie
Mar 7, 2021
Brand new to this and any forum. I kept saltwater tanks back the 1970s and 80s. I now live along an estuary of the upper Chesapeake Bay and am considering the concept of an open loop tank recirculating water from the estuary to the tank and back continuously through buried twisted tubing (as a heat exchanger) for the inlet/outlet. Then stocking with the large variety of fish, invertebrates, and plants I collect in the brackish water bay. Some challenges/ questions:
1. Is this even a good idea?
2. Rise (head) from the water level to my tank would be approximately 40' (30' if I have sump in basement).
3. Flow rate for water exchange assuming a 150 to 200 gallon tank?
4. Pump that can handle the head and flow?
5. Filtration requirements considering steady water exchange?
6. Ideas on aeration requirements/ approach?

I have found nothing about aquarium tanks recirculating water from a nearby body of water. I may simply be using the wrong search words. Any thoughts, experiences or links would be much appreciated. Thanks,
Just now have seen your post, and the one thing which stands out would be possible contaminants, which in the large estuary may not cause severe harm. In a small tank situation would be a problem, smaller space = bigger danger.

Have you found any more useful information about creating this?
Thanks for the reply. I have not gotten any more specific info on looping from the estuary but there is lots to learn about tanks and filters in general. I was thinking of a larger tank, 180 to 200 gallons, with a relatively steady turnover of water back to the bay so was hoping it would be naturally stable with only minimal filtering. The only drawback I have found is that I will need to populate the tank specifically with living things only from the local bay to avoid introducing any non-indigenous species – unless the water comes in but does not return to the estuary. Good news is there are a lot of interesting fish and invertebrate species in the Chesapeake Bay. Seems like someone else has got to have tried this and would have lessons learned.
Closest we got was the kids just finding things in the local creek and ditches and keeping them together in a fish tank. No exchanging of wild water.
A great type filter is the canister FX5 is the older version I have, and it is an amazing filter. There is a FX6 now smarter electronic features and uses less electricity I believe.

FX6 runs 900 gallons edit: but flows through 500+ gallons per hour.

You might want to run one which is cycled just to keep things in the tanks safe as possible
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