Currently I've been approached with a project that requires chilling the water to 70-71F down from around 78. It's a bit tricky though so here we go.
The Marine Biologists, MB for short, want to slow the growth of some opae, similar to grass shrimp, for feed for their Euprymna Scolopes. Basically the shrimp they feed their bobtail squid are growing too fast and they need to chill the water to slow their growth.
The MB first wanted to do a recirculated water type system since we have a setup like that already in which they hatch the squid BUT that would involve filters, a recirculating pump, as well as a UV
sterilizer to stop the growth of algae and coral on the inside of the chiller we've decided to avoid that.
Now we've begun to think on a immersion type system that has flow through of fresh seawater pumped in from nearby. The amount of seawater actually flowing through would be minimal. The actual GPM of the tanks would be VERY slow which is the only reason I thought this might work. The system will be in an old walk in fridge that is located outside. We were planning on putting a window AC
unit to cool the room and coat the outside with heat reflecting roofing material that is painted on to minimize heat from the afternoon sun. It only gets afternoon sun.
The immersion chillers I'd hope to use would be similar to what you'd use when making home brewed beer but the coils would be made out of stainless steel. We'd need stainless to avoid corrosion since it would be running non stop in salt water for possibly months at a time.
Any thoughts on this? Suggestions?
The pictures are of the old walk in fridge from the outside, sideways pic of part of the inside, the temp of the inside at around noon with no afternoon sun on it yet, and the last pic is an example of the immersion chilling setup we imagine.
The coil would be replaced by stainless steel and instead of a tub with ice water we'd have a legit chiller. Possibly one for each tank.