Backyard Aquaponics
A place to discuss aquaponics

The bluegill are about the size of my hand and I have large hands. If I were fishing for pan fish to eat I would have kept 2 of the 3. One is a little smaller than the other 2 but large enough that the bass should leave it alone. The bass are not too big (big enough for me to eat but not really threaten the bluegill). The only reason the bass are in the tank is for total fish mass. I don't know the temp/feed/space needed for them so they are temporary until I can get out and catch more bluegill. I will check local feed stores and order some if needed, for now I think I may go with the shrimp pellets, I'm told I can get them at wal-mart but haven't verified.

my tests from the last few days...

July 31st - noon
Ph 7.4-7.6
Ammonia 0 ppm
Nitrite .25 ppm
Nitrate 40 ppm
Add maxi crop+iron


August 1st - noon
Ph 7.4-7.6
Ammonia 0 ppm
Nitrite 0 ppm
nitrate 10 ppm
Add 5 gallons with ph down
Ph 7.2


August 2nd - noon
Ph 7
Ammonia 0 ppm
Nitrite .25 ppm
Nitrate 20-40 ppm
Added 5 gallons top up water - no PH treatment.


August 3rd
Ph 7.4-7.6
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 5 ppm


August 4th - noon
Ph 7.4-7.6
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm


August 5th - noon
Ph 7.2
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm


I am sitting at a 0 ppm across the board. So the system is cycled? Is the 0 nitrate count an issue for the plants?

The fish have been in for a week now. I have not fed them yet, I read not to feed them for 2 weeks after adding them. Is this true?

I added the maxi-crop +iron 5 days ago. I have seen the yellowing between veins lessen but my cucumbers, pumpkins and squash are still showing signs of a slight potassium deficiency. They where before adding the maxi-crop and do not seem to be improving. Could I have an excess nutrient locking out the potassium? It is a minor issue so I don't think it needs to be addressed yet but I figure adding more maxi-crop would cause a spike in nutrients and potentially cause issues. Any thoughts?

start feeding them, but not "heavily" and continue to monitor your water parameters..
you can gradually increase feed rates as the system matures, just keep monitoring those levels

I wonder if the recommendation for not feeding for two weeks is because they are wild caught fish and might need to be really hungry to take to the pellet feed well. You might try a small feed and see how well the fish go for the feed. If they don't seem interested, wait a while longer, if they are into the feed, then do as Keith says. My experience with getting new fish from a fish farm is you might not feed them for a day or so while you let them recover from the stress of the transfer but they will usually start eating fairly well if conditions are right for the fish and the food not too different from what they are used to.

I would say you are not really cycled up yet because you haven't been feeding so the bacteria might be up to handling the ammonia given off by the fish when they are fasting but as you start feeding you will need to monitor the levels closely since you will be "cycling" up to a new load.

Sorry for being so quiet the past week or so I have been real busy. Anyway here is an update...

August 6th - noon
Ph 7.2
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 7th - noon
Ph 7.2
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 8th - noon
Ph 7.2
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm
Added maxi-crop

August 10th - moring
Ph 7.2
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 12th - evening after lots of rain
Ph 7.0
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 13th - noon
Ph 7.0
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm
Lost one of the bass in the evening

August 14th - evening
Ph 6.4 - took it 3 times
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 15th - noon
Ph 6.6
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm

August 16th - noon
Ph 6.6
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 0 ppm
added 5 gallons untreated tap water

My readings are all still sitting at zeros across the board. Even after losing a bass I had no ammonia spike. I had noticed he was looking a little slow at noon so I checked after work and he had gone. I pulled him out right away. My guess would be the bass are not taking to the pellets as well as the bluegill. I have yet to see a bass eat. I may get some minnows and red wigglers this weekend.

I had a PH drop after losing the bass, it bounced back up a little but not much. I did notice when i dumped in the 5 gallon bucket a considerable amount of uneaten food floating around. I will need to clean that out this weekend but I am surprised it has not raised my ammonia levels.

I am also considering putting a few more bluegill in and turning lose the remaining bass. I'm thinking the zero count is most likely due to an understocked fish tank.

Any thought or suggestions?


I snapped a few pics over lunch I will post here in a few...

that's an awful small tank for bass, I would probably agree with letting the bass go and adding more bluegill. From what I understand the bluegill are better eating anyway even though they are smaller.

With the pH getting down in the mid 6 range, it is probably time to add a sock of shell grit or something to buffer the system since you don't want the pH to drop to 6 unless you have a way of measuring the pH below 6.

oh by the way, just because the numbers say 0, that isn't a bad thing. the plant growth looks pretty good. I would only say you need more fish if the numbers are 0 AND the plants are showing signs of lack of nitrogen and other deficiencies.

My tap water is sitting at 8.2 for PH. I added the 5 gallons today and will add another this weekend. I am hoping that will bring my PH back up closer to 7. I am just wondering why it would drop so fast. I went from 7 to 6.4 over night!

If I decide to add more bluegill what would be a good number for total fish/fish mass?

I have added maxicrop a few times now and still see what appears to be a potassium deficiency in the cantaloupe, pumpkins and squash, even in the wax beans as well. I was actually wondering if I had excess nutrients locking out the potassium. Any suggestions here?

You could try foliar feeding with the seaweed extract too as sometimes it is hard to get the potassium up to certain plants.

If your tap water is really hard I suppose too much calcium could cause problems but I think that is really rare (I experienced it in a system with shells as the media though.)

sudden pH drop can be because the carbonate buffering probably ran out and the pH will then suddenly drop. Your hard tap water is probably providing a certain amount of carbonate to help buffer the pH. A pH of 6.5 is not a bad thing, you just have to keep a closer eye on it because if it drops fast to way below 6 you might see ammonia spike if the bacteria stall out.

How much fish for two half barrel grow beds, Oh, perhaps 6 for your first season. Once you are confident growing bluegill you might be able to handle more since they often get harvested at only 1/3rd of a pound but during your first year, I would stick with less fish and a higher protein feed if you need more nutrients.

Oh, if you need to bring pH up without using hard tap water, you can get some shell grit (like they feed to chickens and laying hens for calcium carbonate) and put it in a stocking and hang it in the tank. When the pH is high enough you take it out, if the pH is dropping, you put it back in. If the pH keeps dropping you swish it about or add fresh grit on the other foot of the stockings with more grit.

Another option for a buffer to bring up pH while adding potassium instead of calcium would be to get some potassium bicarbonate (often you can find food grade stuff from brew and wine making suppliers) This stuff can also be used in water to spray on the plants to provide potassium as well as battling things like powdery or downy mildew.

Awesome! Thanks TC!

With fall fast approaching I have started looking into getting the system in my basement. This will require me to take the frame apart. But I have never grown with a grow light. Can I bring any of the plants that are currently in the GBs inside? I mean, will a tomato plant or strawberries continue to fruit given the right growing/lighting conditions? Will I need to start new plants?

If any one has a good resource for a beginner please share.

There are guys out there with experience growing indoors and using lighting, I'm not one of them.
It takes a lot of light to effectively grow indoors and Florescent lighting is probably only going to be effective for growing mostly lettuce and all the same size since you have to put the light almost touching the plants so not good for growing variety under a single light fixture (and the light figures need to pretty much cover the entire footprint of the growing area.) Some form of HID is usually as effective watt for watt as florescent and better for growing taller/variety plants.

Moving a tomato plant could be difficult depending on it's size. Strawberries could likely be moved, I'm not sure how well they will produce, I think they will want a chilly dormant period before they will start to produce again.

I don't know what the temperatures in your basement will be like but you may want to choose veggies appropriate to the likely temperature range (most of the cool weather crops are actually my favorite crops for Aquaponics, stuff like broccoli, kale, swiss chard, spinach, lettuce, celery, beets, turnips, radish, snow peas, etc.) Of course here in FL during out HOT season it is too hot for many things including tomatoes.