Water Quality Graphs

I finally got around to transferring my water measurements onto a spreadsheet. Bascially, when you have time to do this, you know your system has stabilized!

For those that are interested, below are my pH, amonia, and nitrate measurements. Unfortunately, they only go back about two weeks. There were some pretty major disruptions to my system in the time before then (gravel switch and then the tank repair job) so who knows if even those measurements would have been very meaningful. I know they would have made for some interesting charts, as my pH got up to 8.6 several times when I had the old gravel, and my nitrates ventured into 160ppm several times which led me to do some water changes.

I think these graphs capture the "tail" end of the maturation of my system, as pH, amonia, and nitrate all appear to abruptly stabilize. I have not added any phosphoric acid since last Saturday (5 days ago), so I think we're in for some smooth sailing.






Very bad news on my fingerlings. Last weekend, I pulled the floating basket up out of the water to check on them and found several dead fingerlings. This led me to semi "panic" and I decided to give them a salt bath. I had seen recommendations on giving finegrlings a salt bath once a week, but I do not know how much salt is the right amount. If I measured correcty, I gave them a 10% salt bath for one hour. I then put them in the sump, not back in the floating basket, which seemed a bit constraining.

Every day since then, I or my caretaker has pulled anywhere from 15-30 dead fingerlings off the pump filters in the sump. I do not know what is killing them, but I'm pretty sure they will all be goners at this point. Whatever it is, it is not affecting my big fish (so far, knock on wood).

I definitely need to identify the source of the problem so as to not repeat it. In the meantime, time to find more fingerlings or play some romantic music for my big fish to propogate again.

So far, so good.

There is not a whole lot to update this week. The plants are looking really good. Growth is very noticeable. The color is deep green and healthy.

My fish tank appears to be suffering through an algae bloom. I constructed screen covers for the whole thing and for the sump tank. I also put a makeshift lid on the swirl filter. Hopefully the algae levels come down in a few days.

Water PH is 6.6 and is holding. Haven't added acid for 1 day now. Amonia is at 0.25ppm and nitrates are around 10ppm.

Here are pics of the various plants:

Basil. This is what they looked like when first planted 6 weeks ago. (originally planted in the bathtub bed, and then transplanted into this grow bed.

That's a lettuce trying to come up under the shade of the basil plants. I should have moved it to another area of the bed where it would receive more light, but forgot. It's doing OK regardless.

Basil, three radish plants, and rosemary.

Rosemary, mint, oregano, purple basil.

Lettuces and spinach, 1 week after planting. Most are noticeably bigger than when planted, others do appear to have "taken".

Tomatoes and sweet peppers (left hand row), other stuff are various herbs and spices.

More lettuce and spinach.

Back in Business

Got my fish back in the main tank and got the swirl filter hooked up this weekend. My main tank had required a repair job prior to being able to convert to a CHOP system.

I'm very glad to have things back to "normal". Having the fish in the sump required me to run one grow bed at a time, and I was constantly worried about the fish stressing out in the smaller space and with the drastically changing water level.

Pictures of the fixed tank and swirl filter below. Also, I decided to go with a much simpler and less costly sump container. It is now a much bigger hole lined with pond plastic liner. The first picture shows the sump. It only looks dirty because the liner is clear and the dirt you see is the earth underneath the plastic. You can tell it's crystal clear by how visible the pumps are underneath the water. This plastic is used in commercial tilapia farming, is UV-resistant, and is supposed to last 5 years. I think I'll get a little more out of it in my semi-shaded and small-scale operation.

Tank repaired. Here is what it looked like during the "surgery". The floating basket is for my fingerlings. There must be 100 or so of them, but I have not counted them (nor would I know how without putting them in mortal danger). That 3" pipe is an overflow pipe for the tank to drain into the swirl filter. It extends to the bottom of the tank, where there is a 3"-2" reduction. This helps it grab solids near the bottom and send them to the swirl filter. The reduction adds some suction power I am told, but I have yet to confirm this. Since there is no vacuum created, I do not quite see why a reduction would increase suction, but then again, I am not a fluid dynamics expert. I think the amount of suction would depend on the amount of water being pumped into the tank, since this determines the amount of water leaving.

New Sump. The Fish Tank outer wall is to the left. Don't let muddy floor fool you - it's transparent lining over a hole in the earth.

New Swirl Filter. Water is gravity fed from the fish tank the via the 3" overflow pipe which discharges water about 2/3 of the way down the tank in counterclockwise direction. It exits through a 2-1/2 " inch "funnel" near the tope of the barrel which is connected to a 1" drain pipe that send the water to the sump. This type of filter works in two ways: first, by discharging the water below and making it travel up, that provides time for solids to fall out of suspension; secondly, the swirl effect caused by the vortex in the middle causes water on the outer perimeter to spin much more slowly than water in the middle, also providing time for solids to fall out. Once in the sump, water is pumped both back into the fish tank and to the grow beds.
The barrel is a "blue barrel" of about 200 liters.

The run from the fish tank is long and awkward, but that's what the space I have allows. I've wound up changing much of the original plans, but I think it will ultimately make for a better system.

The plants are doing much better now that the PH levels are under control. They appear to be growing more quickly and are definitely greener and more healthy-looking. I got a handle on the situation starting last week, with the careful addition of phosphoric acid. It still has not stabilized, but I believe it is on its way. Washout from the gravel is completely ruled out as affecting the PH. A sample of the gravel soaked in water yielded stable PH after a small addition of phosphoric acid, and held over a week.

Below are the latest pictures of the plants. The squash plant died back when I transplanted the plants from the bath tub to the large grow bed, and my jalapenio plant died this week. That one had already been dying in a dirt pot but revived in the AP system - until this week. Now it really looks like it's kicked the bucket.

I am not dissapointed by the plant results. AP system take a while to stabilize anyway, during which time plant growth is weak. That, plus the PH problems in the beginning and the transplant of the bath tub plants did not lead me to have evry high hopes to begin with, so I am pleasantly surprised.

My next plan is to set up a floating raft system as part of this system. There is plenty of space for it and it is reported to be the best way of producing lettuce. An additional filter to take finer solids out before sending the water through a floating raft system will be needed.

Click here to see what these looked like when first planted into the bath tub bed. They were transplanted from the bath tub bed to this bed 2 and a half weeks ago.


The bath tub bed went back into operation this week. I could only run two beds with the temporary sump/fish tank. Lettuce and spinache (barely visible here) were planted. Can't wait to see what they look like next week!

Minor Surgery, Swirl Filter and PH Woes, Nifty Screens

My swirl filter turned out to be a partial success. That also means it was a partial failure. The problem was with the drain pipes from the tank to the swirl filter. These pipes were a "left-over" arrangement from when I had my system set up with the grow beds emptying into the fish tank. The water returned through these 1" pipes into the tank.

With the CHOP system, these pipes were to act as overflow drains so that the tank water could fall into the swirl filter and then into the sump. The problem is that I had too many 1" pipes too close together, and there was not enough concrete between some of them, resulting in some serious leakage. When they acted as drains from the grow beds, there wasn't a problem since the water in the tank was never close enough to the pipes for there to be water leaking between them.

The only way I could think of to fix this problem was by removing the pipes completely by knocking the tank wall down to the pipe level, replacing them with one 3" pipe, and re-pouring the concrete tank wall. Then I'd need to wait at least a week for the concrete to cure enough before applying tank sealant, which itself will require another 3 days to fully seal.

Of course, this would mean draining the tank and coming up with a makeshift tank and aquaponics arrangement in the meantime. I removed the blue barrels that were acting as sumps and replaced them with my third cattle water reservoir container. This is now in place and receives the grow bed water. So, we're back to the original type of arrangement while I wait for the concrete to cure.

Current Tank - Grow Beds Drain Into Tank. Former Concrete Tank Undergoing "Surgery"

New 3" Overflow Pipe and Repaired Tank Wall

Swirl Filter

The swirl filter worked pretty well. I used a discarded washing machine drum and fitted a pipe down the middle. The pipes from the tank (the 1"-ers) I connected to large 3-inch pipes that went vertically downwards into the tank. These I drilled plenty of holes into the bottom so that all the tank water falling into the swirl filter would be coming from the bottom of the tank, where most of the particles are. The over flow pipes were connected to elbows and extended so that when they drained into the swirl filter, they entered the filter all the way at the bottom. This would force the water in the tank to travel from the bottom all the way to the top, and allowing for the maximum distance possible for particles to drop out of the water before the water drains through the stand pipe.

Washing Machine Drum Acted as Swirl Filter. Sorry I didn't Get a Picture of it When Fully Set Up

Although it only ran for a day and a half before I had to shut everything down due to the leakage problems, it collected quite a layer of particles in the bottom. Unfortunately, these washing machine drums are not made with the same fittings as PVC so in addition to my tank leakage problems, there were also leaks in the swirl filter.

In my next version, I'll just use a portion of a blue barrel. The principle works quite well, which is all that matters. The washing machine drum will have to find another use.

PH Woes

In the meantime, PH levels continue to be high (8.2-8.4). This is after changing the gravel with gravel I had already tested to ensure it would not raise the PH. I can also rule out the concrete in the tank since for the last week no water has been in contact with any concrete. I've gone from trying to lower it with lemon juice to using phosphoric acid. Every time I lower it (to say 6.8-7.2), it just climbs right back up to the 8.2-8.4 range in a day or so. I've also changed a good portion of my tank water (on several occasions when my nitrates were too high) with water from the spring which has a PH of 6.4-6.6.

I have to say I am completely befuddled. For now, I will continue to lower it by adding a little phosphoric acid every day. If there is something in the water that is buffering the PH, it will eventually be neutralized by the phosphoric acid and then I can keep it at a lower PH. That is the hope, anyway.

Removable Greenhouse Shades

Since I've had extra time while waiting for the tank to cure and so forth, I decided to install some greenhouse shades.

My greenhouse consists of a double-pitched roof, with one side pitched about 3 feet higher than the other so that there is a natural exhaust vent for hot air to escape through. The roof is transparent polycarbonate roofing sheets and the sides are wrapped in anti-aphid screening.

When I first installed the roof, I thought it would be a good idea to also seal the roof on the inside with anti-aphid screening, since there are gaps and cracks in any roof that may allow bugs in (even though it may be water-tight perfect).

It turns out that is not such a good idea. The screening material is white, and when installed horizontally, it makes the inside of the greenhouse painfully bright - to the point you do not want to be in there.

I decided to remove this material, and also looked into installing some shade material over the plants. After researching typical greenhouse shade material by talking with a local provider, they told me the most I want to shade is by 50%. Shading material comes in different "densities" allowing you to block anywhere from 50% up to 99% of sunlight, and what you use depends on what you're trying to grow. Leafy vegetables, tomatoes, and just about everything else I have need lots of sunlight, so there is almost no reason to shade at all. However, I wanted to be able to put something up, if only for when working inside the greenhouse.

I devised a removable shade clamped on PVC pipe and hung on wires. So far, it works pretty well. I can make the shade open or shut by pulling on one of two sets of ropes. It works just like a horizontal curtain. It took a while to figure out all the "bugs", but now that I have one quadrant of the greenhouse done, it won't be too difficult to do the others.

I also decided my fish needed some shade. They are supposed to prefer dark spaces, plus all the sunshine promotes algae growth. This makeshift shade will do for now:

Moving the fish to the temporary tank I assume was pretty stressful on them. Unfortunately, one of the bigger fish died. So far, it looks to be a one-off incident as none of the others have died and that was three days ago. The good news is the fingerlings are doing quite well. I know you are supposed to separate them from the grown fish, but so far they do not appear to be being eaten. Here you can see three different sizes of fish:

The "Everything-Got-Changed" Video

Well, we managed to do all sorts of work this weekend:

• Took down the large grow bed, cut the table legs down, and refilled it with new gravel.
• Installed a second large grow bed and changed the gravel in the bath tub grow bed.
• Dug a hole for our sump tanks. These are two interconnected "blue" barrels.
• Built a steel, lockable lid for the valuable equipment area.
• Built a swirl filter and stand.
• Reconfigured the pump to function out of the sump, from where it fills the tank and the grow beds, in a "CHOP Mark 2" setup.

In all, too much to write about, so I made a video:

The PH will probably take some time to come down. It hasn't yet. I've added lemons and will add a few a day until it does. And if this gravel turns out to also be bad, I just might put myself in the sump tank and bury myself in it! I tested it first, so this unusual AP maneuver should not be necessary.

I'll fix the problem with the overflow system next week. I'm also glad I can now route the drain pipes around the outside of the grow beds. I can walk up and down and across the greenhouse and between beds without worrying about pipes.