Backyard Aquaponics
A place to discuss aquaponics

Hey guys! After watching video on Robs backyard aquaponics on where he washed out one of his media beds it made me go have a good look at mine, at which I realised I may have to clean them sooner than expected. It got me wondering if I should put (2) RFF filters between my FT and garden bed. (As I have 2 slos)



This is my current setup, 2x 50 drains overflowing to the garden beds.

My question is, would placing a RFF filter inline with each drain cause a significant flow rate drop? And is there a way to size it, to reduce this risk?

I was thinking of 2 50L buckets (like the ones pool chlorine comes in), with a cut down blue water tower bottle upside down inside, to use the cone for the solids removal. Then of course a small bell. Hard to explain.. but hopefully enough to give an idea. Maybe too small, I'm not sure.

Thanks all!
Trent

My understanding is that the water needs to be in the RFF for 20 minutes minimum , so the size of your RFF would be at least one third of your water flow rate if your planning on putting all your water through it .

I built a little RFF of to the side of one system as an experiment and just put a small flow through i was amazed how much it caught particularly those fragments that don't sink or float certainly cleared the water a lot .

I have also used them to clean up the water before a raft bed .

I think they have a place

My climate is similar to yours periods of cold weather when the fish don't feed and periods where they eat everything we throw at them , having something to balance the high and low fish waste cycles would be handy .

I cant see the point in taking most of the nutrients away from our grow beds when we are growing plants in them , but being able to manage them would be a good thing .

Cleaning out growbeds isn't hard just do one a year or one every 6 mths

Make sure you have worms in your growbeds

When I reorganise my system I will have a RFF that can be used or taken off line .

Trent's other thread if anyone wants to look at the setup - http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=26541

Twenty minutes?! Noooo, I read one minute minumum, preferably two. My homemade RFF has about five minutes of dwell time and does an awesome job.

I was worried about taking nutrients out of my system, especially the minerals and micronutrients that are concentrated in the solid wastes, so I set up my RFF to feed into an aerated mineralisation tank. It seems to be working OK as far as transferring the solids into the MT sort-of-automatically, and hopefully it's doing the job of returning the nutrients into the system as well.

20 minutes would mean an awfully large filter if you were turning a 2000 litre FT over once per hour with continuous flow- ie nearly 700litres!

Ouch! 20 mins needs another 1000 tank! I hope not... im overflowing around 55L a min, means 1100L :0

Just as well you dont need 20 minutes Peak flows through my swirl filter reach 170l/min, and it only holds ~100l, and up to ~120l at peak flow.

Hmm curious! Do you find it restricts your flow?

I already struggle getting enough flow for my drain so I'm really hoping it wont be a huge restriction..

Thanks everyone for your input! Also, thank you for the system link, I didn't even think of that!

It is open at the top, so there is no flow restriction due to the swirl filter- water comes in via 2X 50mm SLOs, and exits via 2 X 40mm and 1 X 25mm poly pipes. If there is a restriction in the GB delivery pipes, snail, frog or whatever, then the swirl filter can overflow, currently onto the ground, but I'm planning to put an overflow pipe that joins to the main drain to the ST. However, I'm wanting to put a swirl filter with a dip in the bottom to better collect solids, so haven't yet done it, to avoid having to do it twice.

rob bob (and ergo paul van der werf) used roughly 1 minute retenyoon time (not 20). My RFF retention is around a minute and it collects a lot of solids. not the finest stuff, but i use a series of filters. rff -> mesh- > mbbr so it works well for my needs.



https://www.youtube.com/watch?v=RVzNcU8EnwU

That is a good sign. I dont need to pull everything out, gives the worms something to eat. Hopefully ill have enough retention time.

Using waterfall expanding foam i made a sloped drain at the bottom, then smoothed it out with aquarium silicone.

Once it cures, in it will go. Hopefully makes draining it a bit easier.

Thanks for the advices!