Hello fellow green (or shades there-of) thumbs, I would like some feedback on the layout for these flood-and-drain style growbeds in a soon-to-be-built 20’ greenhouse. Half, that’s right, HALF of my current food budget goes to salads, so lettuce/cucumber/tomato are all very important for me.
Water will be pumped constantly from my ~1000 gallon rainbow trout pen which will also supply the nutrition. I’ve done some aquaponics in the past successfully, but this is my first stab at a larger setup and my first greenhouse, so all critique is welcomed.
I’ve got no feedback but I’d love to see it when it’s built. Tell me more about this trout pen
I’ll be sure to post shots when it’s done. I’ve raised tilapia in small numbers in my previous setup, having moved away from a tropical weather locale to a place with seasons, I’ve decided to switch it up to rainbow trout. I’ve recently completed the pen, ~10’ in circumfrence, `3’ deep with ~2’ in the ground. Previously I used an IBC water tank as the fish pen so this will be a large step up.
I’ve heard that trout don’t do well without a current. Planning to include a circulation pump to keep the water moving? (Or am I misinformed?)
Yup that is correct! The vortex created by the pump (that pushes water away from the pen and to the growbeds) should be enough for circulation from the research I have done; however, I may need a secondary one if the fish are unhappy, time will tell.
Rainbow Trout are very sensitive to dissolved oxygen content and temp. The kill temp for rainbow trout is only 77F(25C). I fear the water return from the greenhouse in the summer may be warmer than that. How do you plan on mitigating the temp?
Honestly Talipa may easier to raise. Pond heaters are relatively inexpensive versus chillers.
Of course catfish with their extreme survivability were popular a long time ago with aquaponics.
Yup totally! Temp mitigation plan is having the water underground in an area with 100% shade, also the area I moved to has (typically, who knows for the future) mild summers. I’ve researched a bit and have found lots of ppl locally having luck with trout. When I was in a tropical area I did channel cats (I also love to eat them) and had great success.
I’m more curious about your filtration loop.
Is your intention to have separate filtration or filter through the soil only?
Hey! In previous setups I have filtered through the grow medium (hydroton, expanded clay pebbles) and the roots alone. With the research I have done I will probably have a simple gravity filter (vortex or the like) to start and maybe layer in something more as needed.
I’m looking at doing a smaller setup indoors with a 200 gallon tank and a 40 gallon sump with a return back to the tank and to plants that return to the tank also.
Do you run a sump tank first or straight from the pond to filtration?
Hey there… On my last build that was approx that size I didn’t use a sump, just direct flood and drain from an IPC container over the split 55 gal drum on top. I was in a warmer climate so I was able to utilize crawdads for cleanup duties, I’m sure that influenced my setup. Worked well, produced well for it’s small footprint:
The most important thing for me personally was building up a solid colony of the ammonia eating microbiome before adding fish.
That’s awesome, were they “full size” crawdads or minis AND were you eating everything or just playing?
Thanks! They were blue crawdads and unfortunatley I don’t remember if they were minis or not, sorry. Yup, I ate the fish and the veggie/fruit harvests.
For a 1000 gallon trout system, you’ll defintely want more than just root filtration. Trout produce way more solid waste than tilapia. I’d recommend a radial flow settler before the growbeds to catch solids - otherwise you’ll get clogging issues in your flood/drain system. Been there, done that, had to rebuild my whole setup lol.
