Backyard Aquaponics
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Flow travels
Fish tank > grow beds > Sump (pumped back to FT and DWC)
I built a filter box and it really did not work. I took it back out.



I would like a filter to works for fine solids and hopefully one that has the least amount of cleaning.

What works best for fine solids? My grow beds take out the large stuff.

I looked up many filters but most do not have the same flow as I am doing.
Someone used an up flow filter with bird netting does that work for fines?
Someone said to use a swirl filter will that work for a fine filter.

I found this filter. Does this look like a good design?
Where it says from fish tank mine would come from sump tank.

Hi Mark, can you explain a little more how the flow worked in your original design?

Water flow goes Fish tank > grow beds bell siphon > Sump (pumped back to FT and DWC).

In the picture of the old filter the pex coming in from the left is from the pump in the sump tank.
The right side was to the DWC. Hope that helps.

I would like to add a better filter just before the DWC that would take care of the fine solids.

It might work but would be a pain in the ....

You really want a Static Upflow Filter for this. It's very simple and easy to clean. It's just floating plastic media (K1, K2, Bottle caps .... whatever) in a barrel. The water enters at the bottom and exits at the top, after passing through the media. Varying the media size or thickness of the media layer filters finer or larger particles because it varies the size and length of the channels and it also makes it more or less likely for solids to be trapped. Air is usually used to clean the filter. Here's an almost complete 20 gallon version that's slightly more complicated because it uses an inner bucket, I like doing it this way but you don't need this (Dasboot uses bottlecaps and a 50 gallon blue barrel).









In this one, the water will come in through the top pipe and flow down and in through the bottom of the bucket where the media will be. Water will fill the bucket and overflow through the atrium grate into the bottom pipe. There will also be a drain for cleaning (which will go into the bottom of the outer container and flows to the mineralizer) and an air line will go to the bottom so that the media can be agitated to release solids when cleaning. Basically you'd shut down the inflow, turn on the air and after agitating for a few minutes open the drain.

This is essentially a 3 dimensional sieve. It does require regular cleaning but how often depends on the size of the filtering area and the amount of waste going through.

Hi Mark, I like what scotty is proposing as well. On another note, I hadn't had a chance to go through your system posts yet but got sidetracked this morning by starting at the beginning! Looks like a fantastic setup and I really enjoyed reading about your build from the start. Nice work!

@ jholmes Thanks.

@ scotty435 Thanks for the reply.

My original bin filter was made out of a 27 gallon bin.

I could add the net pot and media and atrium grate do you think this would work?

I can just start over. But if I take out green filters out and add K1 and K2 media? Do you think that would work.
I have a 1 1/2” drain in the bottom of this all ready.

It will work in your 27 gallon tote. I would take out the green filters (messier to clean and not needed) and use the K1/K2...or bottle caps. You can do it with or without the net pot but I think in that container I'd go without - just cover the inflow, outflow and drain to prevent the media from escaping the container. Water comes in low and shouldn't agitate the media when it does (if this happens it creates channels and allows more solids through so it's not wanted). The atrium grates may not fit the pipes you have but you can attach net pots using Zip ties (or just drill holes in a capped pipe) if all else fails. I like to allow plenty of screen area because the media will block some of it. FYI when I talk about K2 it's like K1 but with five spokes (I'm not sure it's true K2 media though) - like here - http://www.ebay.com/itm/like/221298358461?lpid=82&chn=ps&ul_noapp=true

As I mentioned though you don't need anything super special but it should tumble because that makes it easier to clean.

You don't have to add an airline but it's nice to have one. If you don't want one you can clean the filter by agitating it with water instead or just stirring with a stick or something to release the solids.

Thanks so much for your help.
Do you think 2 cubic feet K2 would be the right amount for this? They list K1 Or k2 is one better than the other for fines?

They both work well but other things work just as well or better. Each has it's unique challenges. For example, you could use floating plastic beads but it would be tougher to keep them out of the outflow and other pipes. The plastic beads would filter finer particles using a thinner layer because the gaps are small. Bottle caps are sort of the opposite end, large media, large gaps, easy to screen but you need a thicker layer.

OK so I used the K2 media because I had it already and I got it instead of K1 because it has a fifth spoke and isn't as easily crushed as the K1 (it also has slightly more surface area for bio-filtration - which isn't really what this filter is about but I'm getting to that). The reason I already had it was I use it in a Moving Bed Bio-Reactor (MBBR/aka MBBF) and if I need additional biological filtration it's convenient. I'd still probably just buy more if I was setting up another Static Upflow Filter though. FWIW I suspect the ideal media would be round with no openings. This would reduce the anaerobic areas where denitrification could occur (which loses us some nitrogen and adds some toxic gasses but we might gain some things too). My point is that this does function as a biofilter, more so if you let it sit without cleaning. We mostly want the solids filtering so don't let the filter sit for a really long time without cleaning it and it should be good. If you need to go on vacation, have a light fish load and you're not feeding while you're gone you can probably leave it for 3 weeks without cleaning. If this were going back to the fish tank right away I'd have some degassing done (like an MBBR) because of the possible H2S, ammonia and methane with a long absence.

2 cubic feet is about 15 gallons worth and it's going into a 27 gallon container - that's probably enough (about 55% vs the 60% fill rate I've seen suggested around here). Truthfully though, I don't concern myself with this volume needed number that much because it should change with the opening size of the media and we don't need it to be perfect anyway (and your container probably won't be completely full either).

Initially all the media will float up more than you want but it will eventually settle in and work better after this break in (takes a month or so). You may not be able to get it all in the container at first.

Sorry for the long winded explanation

Thanks again for the info.
I just ordered 2 cubic feet K2 for my new filter.

I built my filter upflow filter.

viewtopic.php?f=18&t=24884&start=555#p546366

It seems to be working very well so far. How do you know when it needs cleaned out?
Do you test the filters PH? This is all new to me. It is my first filter in the system except a radial flow filter. That one was simple to know when to clean out.

Replied to your question in the other thread but basically I think the filter will work better without the netting.

When you say "fine solids" just what size of fines are your wanting removed. The best way is to say what size is in "Microns"

Simple SS wire mesh screens can take care of that.

Water flow goes Fish tank > grow beds bell siphon > Sump (pumped back to FT and DWC).

The solids were collecting on the bottom of the bed.

So the only thing left is fin solids. The new filter is taking care of this so far but I like the idea of a SS screen on the bottom of my outlet bucket. That would take the place of my shade cloth and be easy to clean.

I did a quick search there are a massive amount of screen sizes.

Is this the size you are talking about?
http://www.sustainablesupply.com/Wire-C ... 5-C1726828

If not what size would work for this?

[quote="markbI did a quick search there are a massive amount of screen sizes.

Is this the size you are talking about?
http://www.sustainablesupply.com/Wire-C ... 5-C1726828

If not what size would work for this?[/quote]

30 Mesh is quite large, = 595 microns. Human hair is approx. 100 microns, a coffee filter is 10-20 microns.

Go to the following chart. [url http://www.universalfilters.com/MMCC.html[/url]

Mesh to micron conversion chart

U.S. MESH - INCHES - MICRONS

Here is another good read and shows you different types of mesh sizes in Microns

http://www.utahbiodieselsupply.com/blog/stainless-steel-micron-rating-examples/

The students I, coach start with a 70 mesh, 210 microns for the first screen and then a 10 mesh, 2,000 microns for the final screen. By the way this is all done continuous thru out the day and nite using a air-lift pump before the bio-filter.

We got the idea from a You tube video " homemade sieve filter for pond with 3 chamber 1 of 4, 2 of 4, 3 of 4, and 4 of 4.

https://www.youtube.com/watch?v=QE15or0Enic