Growing Fish in a Recirculating System: Advanced Teacher’s Workshop An Inexpensive Recirculating System Blan Page & PJ Waters

System Components Three (3) 100 gallon stock watering troughs Two (2) 55 gallon barrels Pipe, valves, fittings – 1.5” – 1.25” – 0.75” – Special fittings ” x 5/8” hose barb 0.75” threaded Tee Submersible Pump Cable Ties Garden Hose 5/8” “Light grate”

Where To Get it?? Troughs – Purchased at local Feed & Seed store for under $80.00 each. Can find for less, just have to look in your area 55 gallon barrels – Donated by Coca Cola Pipe, valves, fittings, Light grate – Local plumbing supply and hardware stores Pump, Bulk Head Fittings, Bio Media, Mechanical Sock, etc. – Aquatic Ecosystem Other places/ideas exist

The Tanks Come with threaded fitting (1.25”) Make sure the BHF in the tank is tight – Many times they will leak b/c they are not secured at the factory – DO NOT over tighten

The Barrels Have a 0.75” threaded fitting in the tops Not used in this instance, but could be to put an external pump in place Make sure that you ‘chock’ the mechanical filter when you get it installed – Use a 2x6 on each side – Build a box frame – Etc.

Simple instructions You can start where ever you want We started with the mechanical filter and a tank to get good measurements

The Mechanical Filter Two 90s (1.25”) nested One tail piece to go into barrel Pipe height will determine water level – WHY?

The Mechanical Filter/Pump Opposite end of the barrel Cut out for pump

The Mechanical Filter/Pump Insert Pump How to attach – Catalog indicates a 0.75” outlet – Doesn’t fit? – Improvise

The Supply Side Use a threaded 0.75” tee, a 5/8” X 0.75” threaded 90, and ” valves Why 2 valves?

The Supply Side Here you can see the Mechanical filter (lower left corner), one of the 2 valves you just installed and the pipe leading to the biofilter

Supplying the Biofilter Measure carefully Use the model

Supplying the Biofilter Trace out the inner circle of the BHF gasket Carefully cut out line with jig saw. No need to look for a hole saw.

Supplying the Biofilter On the inside of the supply side BHF to nested 90 turned up

Supplying the Biofilter On the inside of the supply side cont’d Up to Nested 90s Down to bottom of tank

Flood Prevention Step No guarantees, but drilling a small hole in the center of the nested 90s will allow for a siphon break in the event of a power failure. Keeps the water in the barrels and off the floor

Supplying the Biofilter Once the hole is drilled Install and cut a length of pipe long enough to reach the bottom

Use a BHF (1.5”) MPT X SLP Tee 2 Caps Measure carefully – Try to center tee – Cap the ends – Use slotted pipe to screen biofilter material Draining the Biofilter (inside the unit)

BHF to MPT X SLP Nested Valve This valve is screened inside so biomedia will not leave Can be plumbed further to drain where needed Draining the Biofilter (outside the unit)

Supplying the Tanks The Biomedia we are using floats Screen the supply line so it doesn’t escape Just like the drain Measure carefully to center Allow arms to be long enough to just fit inside the barrel MPT X SLP to BHF

Supplying the Tanks Cont’d Further contain the biomedia by adding a piece of lighting screen Sometimes easier to cut 2 halves and then connect with cable ties Makes it more difficult for unoccupied hands to access and subsequently spread media across your hatchery

Supplying the Tanks This shows the system with 1 tank (capped end for expansion) MPT X SLP Nested 90 down turned Into 45 to sloped pipe To Tee, down turned (could use sweep) Valve at every tank for flexibility Then continue to next tank MEASURE CAREFULLY – Your are relying on gravity here and need to not have uphill

Draining the Tank This is the end tank in the line Cap on down stream end allows for easy expansion – Leave enough room to cut then glue new piece MPT X SLP Nested Valve Nested Tee

Draining the Tank Tanks flow into central drain line Into stand pipe Design differs from photo here – External stand pipe is lower for more reasonable water level

Design Changes from Model Supply Side to tanks Recommend moving supply side to a position over the mechanical filter – Provides better access – Centralizes plumbing Pump Selection – Pump provided will run 3 tanks at ~ 1 turnover per hour – If you desire more flow or are going to add tanks consider adding a stronger pump