Backyard Aquaponics
A place to discuss aquaponics

Hey, I'm new to aquaponics and I'm trying to design a system. What I'm thinking about trying right now is a system with a 110 gallon stock tank as my fish tank with some plastic totes (food grade) as beds to start with. The main thing I'm trying to figure out is how to get a year-round system going, as it gets pretty cold and snowy here in Utah. What I'm thinking about doing right now is using a roller dolly (I found one that it's supposed to be able to handle 1000 lbs) with the tank so I can move it in for winter and out for summer. (Anyone ever tried something like this? Did it work?). There are a few questions I have:
1. Could I connect a couple totes with pipe and use a single siphon on them? Or would I need a siphon for every bed?
2. What would be the best lights to use indoors that would be sufficient enough for fruiting plants (and hopefully not crazy expensive)? I've seen LED lighting strips for plants that I was thinking about using. Anyone ever had success with those? How many would I need? Right now, I've got a 4ft LED work light that I used to start plants indoors early this year, and it seemed to be sufficient enough for growing greens at least. Could I primarily use that and use strips to supplement?
3. (And this might be a stupid question) I've heard that the best water to grow bed ratio for beginners is 2:1. Does this change based on whether your using a flood and drain vs constant flow system?

I know I had more questions but I'm blanking on them at the moment Anyways, any help would be appreciated.

Hey KMS....

1. You can, but it's much easier to have a siphon in each bed.
2. I never use lights, plenty of people on here do though.
3. A 2:1 ratio of growbed to fish tank means you have more fish in less water to support the growbeds. Having more fish tank volume means your system is more stable. One of my favourite systems had a ratio of growbed to fish tank of about 0.1:1, Huge tank, small bed, stocked to the volume of the growbed.

So, would it be best to start of with a pretty small grow bed then? And with a small grow bed would you need to keep the amount of fish pretty low in order to make sure the plants in the grow bed would be able to handle it?

Check out the link to my system down at the bottom of this post.

I have a 150Gal Stock Tank for the fish
Two 50gal Stock tanks that are flood/drain media beds

Be sure that whatever you do for wheels... you go for a heavier weight rating that you think it will be. I have 6 castor wheels rated for a max of 350 lbs each. The wheels started slightly splitting under the weight after a few months. So I ended up using a car jack to lift it up onto concrete blocks. If I had it to do again I would go with solid metal wheels without the rubber coating. Pretty sure mine weighs close to/over 2000lbs with the wood and all. If you had 140gal x 8lbs a gallon = 1,120 in water alone.

My system has been awesome BTW. I just moved back up to Virginia from South Alabama. So now have to close it up for the Winter and am currently turning it into a greenhouse.

Where you are at... you could do something similar. Just add thick wood and insulation for the lower section. Put the one of the long walls facing North and insulate that since it will never see the Sun anyways. Then with the two small walls go ahead and insulate them as well (Adding an auto vent to one of them the are $35 on Amazon). Be sure to put an access door on there. During the Winter you can throw up more insulation onto the roof when the Sun gets low in the sky. Then just make all of the walls to where they can be removed entirely during the Summer. Your plants will do much better that way.

Water has an incredible thermal mass. The rocks in the beds will add a little more. I bed it would do fine for you with minimal heating during the Winter like described. Just leave it in place year round. My goldfish pretty much stop eating when the water gets below 55deg F. So Nitrates plummet in the depths of Winter but slowly dropped in late Fall and cam back up in early Spring.

The Dwarf Blue Curled Vates Kale I had in there just stopped growing during that period and didn't flinch at the 19deg days it saw unprotected... when my water froze over in the tank. My system stayed fully open though. I just turned the water off... threw a tarp over the tank... and put in a space heater until it was unfrozen.

Plants grow so fast in these systems it is insane! My "Dwarf" Kale was not dwarf at all. The leaves off of just two plants covered my entire kitchen counter in a 6" deep layer. Washing is a breeze without soil. Just had to get all of the spiders off of it.

yes... small growbed means low fish stocking. It's not so much so that the plants can handle the nitrates (though that is sometimes relevant)... more because there needs to be enough media volume to handle the ammonia (and nitrites) produced by the fish.

After a while I figured out the base starting point for designing an aquaponics system.

First few steps in order are...

1. Figure out how many square yards of plants do you want to grow? From there it all starts to fall into place.

2. Which growing method are you using? The following are basic estimates...
- For Ebb/Flow/gravel you will need to feed at LEAST 13 grams of fish feed daily. (I would double down on that though.)
- For Deep Water Culture you will need to feed around 60 to 70 grams of fish feed per square yard daily.
- I don't know the numbers for the rest. Obviously don't go full bore on the feeding until the system cycles fully. Step up to it very slowly. Nitrates will fluctuate with plantings... and fish appetite will fluctuate with temps.

With the Ebb/Flow you can let all of the fish waste go strait to the grow beds and mineralize with worms and such in there. Then as the beds mature after a year or two you can add in a swirl filter to slow down the solids accumulation.

For the DWC style you need to add an in depth filtration system to capture solids... then build a mineralization tank on the side to get things broken down... filtered again... and put back into the system.

3. Anyways, Now that you know how much you plan to grow... and how much feed will be needed to grow it... you can figure out how much fish you need... then figure out the size of the tanks(I usually go low stocking density of about 1lb of fish to every 5 gal of water at grow out)... and the amount of biological surface area for filtration required. I always double down on biological surface area as well. If not more than double if possible.

4. Going with ornamental fish in your first system can ease things by making it easier to balance the nitrates/nutrient flow as it will be much more steady and constant. If you buy tiny koi for almost nothing you can grow them out for a year or two and then sell them at a premium. I just sold three 6" koi and 12 4-6" Goldfish for $100 before my last move. It paid for the fish, feed, and electricity for the year. (Way over actually)

It is a bit to learn at the beginning but it's like reading. It comes easy once your brain digests it.

Start small like you plan and complete all of the learning process on something small. Each system afterwards will work waaay better and require less maintenance. Usually simple is the better answer. I add extra things only to minimize maintenance OR increase reliability.

I was an aquaponics maintenance man on my first system. My current system only required occasional water and fish food for the first year.


Marty

That is a pretty amazing setup. How much did it cost you to build?

Is there a way to calculate how many square yards you'll need? I've heard that plants in aquaponics systems don't take as much space as those in soil, but what is the difference? If possible, I'd like to get some tomatoes, peppers, and strawberries out of it, but I know I may have to take a step back for my first system at least.

Growing koi sounds interesting. How many of them could I comfortably raise in 100 gallons if I planned to sell them at around 6-8"? Or would I need to get a bigger tank than that before I even thought about getting koi?

I once had the numbers in my head when I built the system. The numbers are lost now though.

Pump ~ $25 on Amazon - Watch my YouTube vids for the mods I made to it. I also got my auto fish feeders from there... as well as food, auto vent opener(just now), and amendments.
https://www.amazon.com/PonicsPump-Subme ... dpSrc=srch

Stock Tanks - I got them on sale for 50% off but here is a link to what Tractor Supply sells. https://www.tractorsupply.com/tsc/search/stock%20tank

The Two Poly roof sheets are around $25 each at Home Depot. Go with Poly and NOT PVC. Poly is more expensive but will last many years.

If you are just doing a 100gal tank... then just one 50gal grow bed is what I would recommend. Don't want too much water leaving the sump/fish tank at a time.

For a 100gal tank you could probably throw in as much as 15 koi if selling them off slowly. However, you need to add them slowly a few at a time and be sure to actually do the math for bio surface area based on the media you end up using. Keep in mind that they will all have to be sold eventually. If you have a 24" deep tank you can keep goldfish to maturity. The koi would be too big unless you had a 300gal tank or more.

They actually sell a 8ft wide x 2ft deep tank there as well.

What is cool is that if you get the larger sump/fish tank... then later on you can add a larger fish tank and many more grow beds. Just doing a split flow for the water. One split going to the fish... and one to the grow beds.

Since the one I built is on wheels and made to look fancy I used a lot of lumber and it was way harder to build. If doing a permanent greenhouse then you can put one of the long walls to the North and insulate that wall... and the two short walls. Auto opening vents are almost a must for greenhouses. They get hot quick. Even during the Winter.

This is the upgrade I added to my first system that was in a greenhouse. It worked flawlessly for years.
https://www.amazon.com/Univent-Automati ... 2661618011

Good Luck with your build!

I have 13 Goldfish in my 150gal system. They love to school up and beg for food. Always feed by hand at first to get them to associate you with food so that they beg for it... even a 20 minutes after you last fed them. lol

Then you can turn on the auto feeders.

What is cool is they will eat out of your hand after they get bigger.

Oh.. one more thing...

As far as plant spacing goes...

The nutrients are spread out into the water and brought to the roots. So spacing no long applies for that.

However, Sunlight is still a serious factor.

Also, different plants need different PH. Having lots of different plants will actually help you to read the water PH without having to test after a while. You can just read the plants.

And... I always put my longer living plants that get large root systems towards the middle of the bed. So the roots don't pack tight on the wall of the bed and cause dead zones due to food/poo building up in the tighter spots. I kept some jalapeños and bells going for 2 years here in Virginia in my old greenhouse. Certain types of peppers can live for more than one season and just make even more peppers their second year than in the first.

If done right the only amendments you will ever need are iron and calcium. However, I always cheat and start my systems off with dried kelp powder. It tints the water to keep algae down and fertilizes as well.