Vegetables per square foot

[Allisyn Wood]

I understand the ratios between gallons:grow bed square footage (5:1 to start).  My question is how many vegetables can be grown in that square footage?  I have a grow bed that's approx 4'x14" (little over 4 ft sq) and a 55 gallon tank.  In my bed, I have 5 tomatoes (3 that are thriving, 1 that's making a good attempt and 1 that could use some attention), 2 peppers, 1 eggplant, 3 herbs, squash and some seed sprinkles.  Yesterday, my fish were gulping at the surface (after filter cleaning...) and this morning, I had lost several.  My nitrate level is really high, so I am assuming my veg count is too high even though they're all doing relatively well.  So, what's the magic number of veggies per square foot of bed to keep the water balanced? Do some veggies (tom, etc...) produce more nitrate than others (lettuces, peas, etc).

Thanks in advance. Happy eating.

[Chi Ma]

 

Veggies don't produce nitrates. They consume them. Fast growing leafy plants like lettuces and greens consume lots of nitrates. I use them as my nitrate scrubbers. I always have some in my beds. I plant my greens relatively dense. You really can't hurt by over planting.

 

 

 

 

[Allisyn Wood]

Thanks for the reply, Chi.  I thought the plants ate the nitrites and converted them to nitrates.  Guess I have something backwards.  Why did my fish die off? (I realize that's kind of rhetorical.) Just a basic lack of oxygen?  I have two stick aerators, and two constant trickles into the tank? The fish have been in there for a couple of weeks now and just having problems over the last couple of days.

 

In the meantime, I'll get some leafy stuff in to see if that helps.  Great garden!

[Chi Ma]

Sometimes after cleaning the filter there are lots of particulates stirred up and that may irritate the fish. Another thing is that your bacteria live in the filter. If you happened to wash the filter with city water the chlorine and chloramines  in the filter will will kill off the bacteria and cause an oxygen deficiency. 

 

Here is a very basic vid that I had made :)

Allisyn Wood said:

Thanks for the reply, Chi.  I thought the plants ate the nitrites and converted them to nitrates.  Guess I have something backwards.  Why did my fish die off? (I realize that's kind of rhetorical.) Just a basic lack of oxygen?  I have two stick aerators, and two constant trickles into the tank? The fish have been in there for a couple of weeks now and just having problems over the last couple of days.

 

In the meantime, I'll get some leafy stuff in to see if that helps.  Great garden!

[steve]

Nice job on the video Chi

[Rebecca B]

Impressive little video.  Good going!

[Chi Ma]

Thanks.

[David Waite]

Allison it sounds like you have aprox 7.5 gal of grow bed to 5 gal of fish tank if I am understanding your formula. That is a great ratio. I think your fish got ahead of your plants and you now have a high nitrate. What is that number. I would slow way down on the feeding until your fish stop gulping for air and the nitrates drop a little. You can control nitrates with feeding just like ammonia but it takes a while to see the effect. Feed once a day for a while. If you have another pump add some aireation if your fish are still gasping. put a diffuser on the return to break up the water entering the tank even more. If you can put a screen on your pump and loose the filter even better. You just want to keep the fish out not the poo.

[Rob C.]

Nice video, Chi.

 

For Allisyn,

I haven't started my system yet, so take this advice with a grain of salt.  I'm planning on using Mel Bartholomew's recommendations from his book, All New Square Foot Gardening.  It's for raised bed gardening, but it covers a lot of different topics in a very easy to use appendix: plant spacing, plant height, outdoor planting time charts, growth times for different plants, and in depth, but short, overviews of different plants.

 

For example, tomatoes come in two types: determinate (bushing) and indeterminate (vining).  The spacing he recommends for determinate varieties is one plant per 9 square feet (they get really wide), but the spacing for the indeterminate varieties is one plant per square foot.  For lettuce, he recommends a spacing of 6 inches, or four plants per square foot.

 

However, I don't know how well this translates over to aquaponics.  

 

Best of luck!

[TCLynx]

You say the fish have been in the system for a couple of weeks.

Did you fishlessly cycle the system first?  If not, your fish may be experiencing stress from the system cycling up.

To know why your fish died, we need to know

1-water temperature and pH

2-Ammonia

3-Nitrite

4-How often are you flooding/draining your grow bed?

5-how many fish in how big a tank?

 

If the gills of the dead fish are brown, then it could be nitrite toxicity.

[Rebecca B]

And if the gills are red, it's likely ammonia poisoning.

Ammonia Poisoning

Red or inflamed gills. Fish are gasping for air at the surface. New tank setup or a tank with too many fish.

Ammonia poisoning is easily preventable. Avoid adding expensive and less hardy tropical fish until the aquarium has cycled. For more information on cycling your aquarium please read about the aquarium nitrogen cycle. You can use a substance called zeolite to help absorb ammonia but the best solution is to ensure that your aquarium has cycled and that your tank is not overcrowded. If your tank has not yet completed the nitrogen cycle, you will need to perform frequent water changes to keep the ammonia levels down.

[Allisyn Wood]

Hi, A quick update. 

I've let my garden cycle for a few days without fish and the nitrate levels are coming down nicely. 

Yes, I did do a fishless cycle so I don't think it was the stress of that, but much more on the user error side (too many fish, too much food, filter cleaning, too few plants...). 

Levels are:

pH: approx 6.8

Nitrites: <.25

Ammon: 0

I have the pump on continuously, so it floods and drains about every 15 minutes.

Way too many fish as they were fingerlings (bait fish) so I was thinking they would be removed systematically once the boat got afloat.  Got 10 redbreast sunfish fingerlings today.  They will be the only residents from here on out.

 

I am prepping another small bed to have all leafy greens as Chi suggested and I think (hope) all will be well.  Keep you posted.  Thanks for all the advice!  Happy Thursday!

[TCLynx]

I would recommend getting plenty of grow beds going.

I would only stock one fish per cubic foot of grow bed and having between 5-10 gallons of water for each fish.