Saturday, October 30, 2010

Week One: Oh-*hit and Yeehaw!

The phone rang Tuesday evening. It was my caretaker at the farm, where my AP system is. I didn't leave him with with very many instructions, and this is a completely alien concept to him, and just about anyone else in Costa Rica (hydroponics is fairly well know, but aquaponics? - fuggedaboutit). The main reason for the lack of info is he leaves Saturday at noon and I didn't finish getting everything set up until Sunday. I didn't even get the fish until Sunday. So Sunday I left the farm and went back to the "real" world, without being able to give him almost any instructions. I left everything in the hands of fate and my trusty (and well-tested) back-up pump.

The point being is, I knew something had to have happened for him to be calling. Something bad. Dead fish, I assumed.

Fortunately, it was nothing anywhere near that bad. He explained, after much excitement, that one of my larger grow beds (of the cattle reservoir variety) had flipped over. Apparently, one of the footings gave way, causing it to tilt. The massive weight of the grow bed caused the rest of it to flip. Of course, that broke some pipes, sending water everywhere. By the time he discovered it, the water in the tank was near empty. If a few more minutes had passed, my pump would have been sucking air, probably burning out, and the fish would have been toast as well.

Fortunately, he did find it on time, and I was able to explain to him over the phone what to do: disconnect both cattle-reservoir grow beds, cap the pipe, and leave the bath-tub grow bed on. And, refill the tank of course.

I have to hand it to Carlitos, my caretaker. He has no idea what any of this stuff is. He probably did not get past 4th grade (through no fault of his own), does not know how to read, and to top it off, he has a horrible stutter. It took me about 5 minutes to even understand what it was he was explaining to me. Anyway, most people think he's a bit "slow" but it's just the way he comes across. He's actually pretty quick in a fix.

I spoke with him again Wednesday and Thursday, just to make sure everything was OK. He and a helper also poured concrete footings in the spots under each grow table leg. I won't even get into what I had them sitting on before. Suffice to say, there is a reason I don't have a materials engineering degree.

Here's the table that flipped and bent out of shape. It's sitting upside-down on top of a non-damaged table:

Now, the system basically ran for one week. To be more precise, it ran for three days roughly without problems. Then it ran with one grow bed attached for another four days. It's a good thing in retrospect that I only started with as many fish as I did, as I doubt one grow bed, and bath-tub sized one at that, would have been able to handle the amonia put out by a large number of fish.

The Yeehaw news is a result of my tests. Amonia levels are in the sweetspot range of .25 - .50 ppm and nitrate levels are through the roof. Here are my water tests:

I was not expecting nitrate levels to be so high so fast. This is great news as it means I have both ammonia-to-nitrite producing bacteria and nitrite-to-nitrate producing bacteria in my system after such a short time. I can only guess that because the gravel sat in my driveway for so long, and maybe because I have chickens that love to "liberate" themselves all over the place, that I had good levels of bacteria in my gravel to start with.

I'm actually a little worried about the nitrate levels. It does not cause immediate harm to fish - and certainly is not anywhere near as poisonous as ammonia is to fish, but it does seem quite high. I'll have to do some research to find out if I should be really worried or not.

In any case, the solution to high nitrate levels is to add more grow beds and plants. So I spent all Saturday (today) resuscitating one of my larger grow beds. Just filling the thing with gravel is more exercise than I usually get (none). I also hooked up my back-up pump to the fish tank for a while so I could use my main pump to wash the gravel in the grow bed, using another grow bed to catch the water and recycle it through the gravel-filled bed:

There is gravel in the upper bed, I promise! After washing it enough times to have the water come out clear in the bottom, I hooked it up to the system and put my tank pump back. I wasted a ton of water. Good thing water is cheap and plentiful here. If I didn't have cheap water, I guess I would have just hooked it up as is. I would not have been able to see my fish for several days, but supposedly, that doesn't hurt them. I don't know - I like clean water and to be able to see my fish.

I'll probably plant some things in the second grow bed tomorrow. I'll hook up the remaining beds as soon as I can. Unfortunately, only being able to be around on weekends puts a severe slow-down on things. On the other hand, it makes me work my rear end off every minute I'm here!

And now, it's beer-o-clock.


  1. Cheers! Wow, what a story, thanks for sharing. I almost feel like I'm there with you :)
    That's great news about your NH3/NO3 ratio. I can't believe that the bacteria colony was established so quickly. I wonder if they were already present in the well water? Though typically well water's dissolved O2 is really low.
    I think washing the gravel was a good idea. I can't stand Murray's cloudy water, his fish probably think they are living in Los Angeles or something, lol,
    Thanks again for the update....keep'em coming...Jeff

  2. You're right - it could have been the water. It's not well water though - it comes from a spring that pools into a natural reservoir. There are sometimes frogs and a turtle in it (and other things). Maybe that's it. PS: I'll have results tomorrow on the PH fiasco, and hopefully know whether it's due to the gravel or something else (probably the tank sealant).

  3. Hey Patrick,

    I'm sure you thought of this, but did you test the Nitrate level of the source water? That seems like it was way too fast... generally nitrosomonas takes at least a week to get established where you see any trace of Nitrite, and then it takes further time for the nitrobacter to delveop before any nitrogen can be produced by "your" bacteria and detected. You are way beyond trace levels here. Ammonia I get. Nitrates, not so much.

    I would be concerned enough to track this down, because your Nitrate is only going to climb from here unless you add a ton of plants fast.

    You may want to check for iron levels too, as it will help to grow plants fast and remove bad stuff (so you can eat it) ;)


  4. Hey Rog,
    Thanks. I did check rites and rates on 10/23 (Day 1). Both were undetectable. I'm taking fresh plants with me tomorrow which will hopefully take up the extra rates. I've gotta pick up my dog on the farm and bring her into town for surgery so I may as well take some plants out. I'll remeasure tomorrow and see what's going on. I agree this is very strange. What else could be producing these levels of nitrates?

  5. Or, what else could cause this kind of reading (maybe false reading)?

  6. My best guess - you have fertilizer (or equivalent, ehr, um, chicken shit) leaching into your system. Most likely from the grow beds.

    If this is the case, and your chickens can't actually continue to crap into the system, it will resolve itself in time with water changes and plant life.

    It does not yet appear to be at a toxic level since you are not finding fish floating, so I would perform a 50% water change, monitor and keep a chart of where it goes. Unfortunately you are so high on the scale right now it will be difficult to measure small changes, so the water change should shift you towards the yellow color. You can also purchase a high range Nitrate test kit if you prefer, as doing water changes now will slow down your bacteria growth.