Backyard Aquaponics
A place to discuss aquaponics

I started it with virgin gravel Steve. I used squeezings from several fresh water aquariums and a high end bacteria starter liquid. The shop owner says he can start a tank in 4 days with that stuff. I was having nitrites at 2+ then when I changed my water I never had any more nitrites.

Looking at a nitrogen cycle chart I looks like it takes 10 days before nitrates start to climb any, so I will expect to see some nitrates within 14 days (6 more).

i was quite surprised with Emirs cycle rate after i gave him a bag full of my best gravel, right from under one of the pipe outlets. wasn't even a week i don't think.

he's also 0,0,0

Don't be too concerned if you don't get nitrate readings, your plants might be stripping them all out

look at it this way, if you have zero ammonia and zero nitrite and you are feeding your fish then you MUST be producing nitrates but they are being used up by the plants

Today still 0,0,0. pH 7.44

I still do not have my plants in I do have a small screened tray of duckweed floating in the tank.

Just the bio filter.

I decided to set up the plants after I get the fish set in a more winterized location. I am building a small work shop and I decided to put 3 hundred gallon tanks into it to be used as my hatchery. Then I am going to attach a greenhouse to the south end. So long story short, I'm going to be running on just the bio filter for another 4 weeks.

So I will be doing water changes I guess. What is the max nitrate level I should watch for?

Well, I had my nitrate over 1000. That wasn't really a good idea, but it happened. I think most folks try to keep it under 80. You could build an RSG filter if your nitrates start rising too fast.

Yes, I think I will build a RSG filter

Today I did another test. Still 0,0,0 !!

I have 100 gallons of water and 20 fish about 3.5 inches long. I'm starting to wonder where the nitrates are going. I do have some duck weed in the tank.

When I was starting this tank I put some bacteria starter in the tank that I got from the pet store. One the label it shows ammonia and nitrite crossed out with NH4 not being crossed out. I wonder if I might have some kinda of RSG filter effect going on or if the duck weed is stripping out the nitrates.

Its not a problem with this setup because I am stuck on a bio filter without grow beds for a while as I build my fish hatchery shed. However, I do not want to start my grow beds from this bio filter if there might be the wrong strains of bacteria in it.

Duckweed will strip out ammonia, I believe. If you have a lot of it, that could actually be taking a lot of the ammonia that the bacteria could be using.

Don't worry about having the wrong type of bacteria. If you have a food source, the right type of bacteria will find it.

I guess if the duckweed were taking most of the ammonia then the bacterial would not be able to produce much nitrites and nitrates. Its not a lot of duckweed; it's a tray about 12" wide and 30" long

Has anyone tried a cheap swimming pool like this one?

How long do you think it would last compare to the poly tanks?


I was looking at getting two of those 700 gallon blue aquacuture fish tanks, but they are almost a thousand dollars delivered. If one of these cheap pools would last half as long I could buy 4 of them for the price..

Joel had a cheap inflatable swimming pool that deflated in stages over a season or two. It was one of his early prototypes.

I would expect any Walmart pool to last only a few seasons, while an aquaculture tank or stock tank should have a lifespan measured in decades. Looking at my Rubbermaid stock tanks, I expect them to still be going strong when I am long dead. I have learned that it is best to go ahead and get quality products whenever possible. It leads to less frustration and less expense over the long haul. When your cheap swimming pool suddenly splits, how costly is that going to be in terms of damage, lost fish stock, dead plants and time? In my case, it would be most expensive/difficult to replace fish stock since I had my tilapia shipped in from Miami.

Have you looked in to stock tanks? Like some of these: http://www.stockyardsupply.com/page11/index2.html
I would think that your local feed store or farm supply store could get you a stock tank for well less that $1000. Last I knew, Texas still raised plenty of cows.

Good points Janet. I can get the rubbermaid 300 gallon tank for $189 when they are on sale and thats about the same price per gallon as the aquaculture tank. I guess I'll just get the fish tanks; hopeing that they are less likely to leech out any chemicals into the water.

I was going to build a cement tank, but now I decided its worth the price to be able to move the tanks.

The 50gal Rubbermaids make great growbeds, too.

Yes, I have my eye one the 50 gal Rubbermaids

The only problem is price. I would need 64 of those tanks.