Backyard Aquaponics
A place to discuss aquaponics

This is my system I started with the intention of just having a aquaculture setup. But after looking at how aquaponics worked I decided to expand. Because to the plan at the beginning I have a lot of water space and not a lot of growing space. I am working on getting more but I am on a limited budget at this time so it is slow going. You can get more info on what I have done on my blog. http://homeaquaculture.blogspot.com/ Here are some pics.

Like the caties. I've got a mess of them in the pool.

The gravel bed on the blog page - does it drain or continually flood?
I like the cress-in-filter. Look forward to seeing it grow...

the gravel bed is ebb and flow. The pump is switched on for 15 min per hr. Most of my water is filtered by the biofilter and pump.

I have a question about my system plant growth. I have about 1400 gallons of water. With 32 4-6 inch catfish and about 7 Bluegill in it. My water temp is about 50 deg F and I am feeding about 1% of the fish body weight per day. I dont seem to be gettin the kind of plant growth that I expected. My grow bed space is very small in relation to my tank size and I am wondering if the nitrates are too thinned out in the water for good growth? Or if possibly the temp is too cold and I need to bring it up so I can feed more? Or should I just get some gold fish or something to increase the nitrogen in the water? I am gettin a solar heater to hopefully biring the temp up to nearer 70 deg F. I am fairly new to all this and would appreciate some help. Any other advice would help. Also what is Seasol I read about lots of people using it.

Well, what are your water test results?

It can take some time for the system to mature and the plants to do better. Sometimes it requires some supplementation of potassium, Iron and/or trace elements.

That is a huge amount of water for just a small amount of fish.

How long has it been running? Is it fully cycled up?

At that water temp, I don't expect much growth. If you can warm things up a bit, you will probably have better results or if your water temp is likely to be pretty cold most of the year, then perhaps you should think about a cold water fish like trout or something.

I have channel catfish and they grow quite fast with warm water. I actually think channel catfish are better growers in my climate than tilapia. Part of the year the water is up close to 80 F or even warmer like 86 F but we do have cool weather in winter and the water temp can fall below 50 F if no heating is applied and that would kill the tilapia but the catfish are fine. I would estimate that a good portion of the year the water is below 70 F and the tilapia don't eat and grow as much when the water is that cool but the catfish still grow ok with water between 60 and 70 F.

Anyway, let us know about your water tests and we might be able to help you with your plant issues.

Last tests showed Ph 7.6 Ammonia 0 Nitrites 0-.5 nitrates 0. I will test again tonight. This system has been running for 2 mounths and is fully cycled. I have supplemental iron added. I expect that the water wont get much cooler over the wenter. It there a suggested fertalizer to help with the trace minerals?

Maxi Crop would take care of trace minerals and potassium. Just make sure it is the Original maxicrop that doesn't have any added nitrogen (though your plants might want some additional nitrogen, you want to make sure whatever you add won't overload the system.) Sea salt or clean sea water can also provide trace minerals too.

Some people have been known to add a little urea fertilizer to up the nitrates during periods when the fish load wasn't enough for the plants. Others (including me) have done the pee ponics thing though that has it's own set of issues, primarily the yuck factor some people have with it.

Anyway, the sea weed extracts are the primary recommendation for trace mineral and potassium supplementation. Here in the USA that usually means Maxi-Crop, elsewhere Seasol is more available. Clean Sea water or good sea salt also provide trace minerals.

This mornings tests ph 7.6 nitrates 0 nitrites .5 alkalinity 180 hardness 100 temp 50f/10c. These are all approximate numbers. I started chard growing 3 weeks ago and it is only about 2"/50mm tall. They have been that tall for at least a week. I am thinking of getting about 10 big goldfish because they are dirty and should still feed at my temps. However I am a bit worried about the nitrite readings.

Weather is cool may take longer to get bacteria numbers up as fast as ammonia/nitrites. If your fish source is local add the goldies 1 every few days and keep monitoring water conditions. I don't know your daytime highs but 50F is cool even for the plants.

My day time highs are in the 60 deg range but in my greenhouse the get near 90 deg. I just got some maxicrop to help. I was wondering if the compost tea from my worm bed would be good for the tank? I cant imagine why not.

Wow all this adding stuff I don't understand

In a new system changes 1 at a time is heaps better...
Things(problems) can take quite a while to manifest
...so week to week the system water is trying to deal with a sliding scale of chemical challeges

I get that if your fish load is less than waste producing then nothing much will grow.
But why not just add humonia....
Or has this been mentioned before??

mentioned before. I am just fishing for info. I have not put anything extra in my tank as of now but with such slow growth I am starting to think of new ideas.

The new moon is today so more growth above ground will happen over the next few weeks...
... just finished waning so it was root developement stage.

How about a bit of foliar spraying ,, maxi-crop mix with the right amount of water.
You'd be giving the plants what they need AND not messing about with your system as much as when adding to the actual water