Backyard Aquaponics
A place to discuss aquaponics

okay posting God, I did a search and was not able to answer this question.
Is it possible to get a grow bed up and going prior to adding the fish?
I am thinking about taking a trash can with a false bottom and put hay in it and compost material and circulating it through the grow bed. The bacterial should build up in the grow bed just like they do in an under gravel filter on an aquarium. In fact I am going to take some of the black gunk from the under gravel filter to get it going fast. I see no reason to flood and drain, just circulate continually. I believe the bacteria will develope around the crud trapped in the gravel. Once the bacteria is established it should be able to build up to take care of the amonia pretty quick.
I am setting up a grow bed that does not have fish at all, It will have compost in water. I believe the bacteria from the decaying vegitation will do the same thing as the crap from the fish and I can crank up the crap in the water and not have to worry about it killing the fish. From what I understand, I should be able to start off with a grow bed that will produce like a bed that is a year old. Once the bed is going, I can use it to filter a fish tank too.

Any input?

Certainly use the "gunk" from the under-gravel filter Johnny... it will shorten the cycling time...

But why not just go for a standard aquaponics approach from the beginning...

You're already going to put the growbeds/gravel in place... and kick start the bacteria colinisation.... so you can start planting...

A few weeks to cycle... and you'd be ready for fish.... which will continue to supply the ammonia for the bacteria/growbeds...

I see no need for any "hay" or compost... and frankly think that in the long run this will only present problems... including oxygenation... particularly if you run as a continuous flow...

IMO... cycle... use flood and drain.... and add fish..... two food sources, within a closed loop water system....

It's what AP is all about...

If you have a fish tank then when you do a water change put that in the system. This will help give it a kickstart as well.

I'm not going to pretend I even know what is going on it a year old aquaponics grow bed, but I would just venture to say using a compost heap to simulate such would not be the same. Just my two cents, and I have not a clue keep us posted how it works for you.

I am basing all my assumptions of the fact that when I was reading about how Aquaponics, it said it worked by converting the ammonia produces by the fish, waste and other decaying material to nitrites then nitrates. That is three sources, so I just assumed you could use the waste and decaying material without the fish and at a levels that would be toxic to the fish, but not to the plants and get super growth results. You would not have to worry about feeding the fish or killing them. Now don't get me wrong, I am going to grow the fish for sure. I love fish in man tanks. I am the son of a commercial fisherman and I cut my teeth on the deck of a commercial fishing boat. But I only had aquariums and small backyard ponds. I have always had balanced ponds with fish, minnows, shrimp and aquatic plants. I am excited about the Aquaponic way to grow vegetables, not just Aquaponic plants.

Try getting a few goldfish. They are very hardy and cheap so are hard to kill and if they die off then no big deal. Once things are established introduce your normal fish and the goldfish will add to their menu. We used goldfish plus water from other tanks to establish our 600L tropical fishtank in under a week and it worked great, same principle should work on a bigger scale.

Also I'm working on the assumption that until you get some good plants growing that you may need to do some water changes or at the very least keep the initial stock levels with either small fish or not a lot of them.

Well my system has no fish in it right now cause they all croaked but I have good growth going on. My system is only a little over 2 weeks old though. I've already eaten the radish tops twice now.

I just add pure ammonia from the hardware store to the tank and some maxicrop. I figure I'll add the fish when the water isn't black anymore

Hey JM, maybe search for fishless cycling, one way to do it is "peeponics", see ->

I also used fishless cycling with pure ammonia, but it can be hard to find the stuff. You have to shake the bottle and if it foams it has detergents in it that will kill the fish. It should also not have any fragrances added either. I was able to cycle from scratch in about two weeks using ammonia.

My understanding of the science is that the process is linear. There are not three sources for the nutrients it is as follows: Ammonia --->Nitrites ---->Nitrates. The only thing beneficial for the plants are the nitrates. Am I wrong?

Actually mine isn't showing a nitrite spike like it's supposed to. I don't know if I'm doing something wrong or if it doesn't always happen.

dthawk: i also assumed that plants like the nitrates only and agree with your linear process.

DT I read that as fish, waste, and decaying matter being the three sources he's talking about.

I can get the grow bed constructed pretty quick, but I need time and money to do the fish tanks. I was hoping to get all the bacteria established and ready to clean the water in the fish tank.

how would you cycle without a tank? where is the water stored?