Backyard Aquaponics
A place to discuss aquaponics

Dears,

I am installing AP system with one IBC tank and two grow beds (10inch radius 21.5 inch depth) while using clay as media.

The fish to water ratio is 7 pounds of fish to 70 gallon of water. Summer temp can go upto 40C.

I seeking feedback with regard to timing of watering the grow beds i.e. how many times per day it should be watered so that the plant receives adequate watering.

Thanks for your help in advance.

Regards

Taj

Taj,

I have a Flood and Drain system with a 17 gallon GB and 35 gallon FT. I run the system for 15 minutes every hour from 7 am to 9 pm. The GB flood and drain twice within the 15 minute period. So far, this has been a sufficient in circulating water for the fish and keeping the clay pebbles moist for the plants.

-Tyler

I use a timer with the F&D method 15 on / 60 off.

answer = as often as the system requires you to:

#1 - have enough circulation for the fish and fish tank - this is usually more important than what the plants need.
your grow beds are the primary filter - so if you are heavily stocked with fish you need lots of circulation.

#2 - as much as required to keep the media and roots wet. If it hot and dry the media will dry/evaporate quicker.
So you have to work out what suits you system and its location. In a hot-dry summer here in Perth I need
to circulate more water to keep the media at optimal levels and the plants happy.

#3 - the rate that keeps a good optimal nutrient and oxygen (DO) supply to the plants.

the message here is that F&D is not about 'watering the plants', it is about delivering a circulation regime that best supports the system. The pumped water is the major engine of the system.

If you are just looking to the plants than you must basically run a quasi-RAS to make the fish possible
(ie. recirculating aquaculture system) or be running a more classical pond type set up.