Quick chemistry update and Sad news

Two things to cover today.

They are fairly connected, but be warned, they are both chemistry related. It really goes without saying that the moment you enter into Aquaponics, you are going to get to a point where you have to deal with chemistry… My background certainly doesn’t have much formal study with chemistry, but I know some of the basics. I have to admit that I am still astounded by how quickly some of the chemical changes in an ecosystem can change.

I have switched my methods of water transfer between the water reservoir of the Emily Garden and aquarium for the moment to include a more total switch-out of water than the method I was previously using. My “theory” method was to have 2 pumps pushing water both from and to the aquarium and Emily Garden, and let water diffusion take care of the balancing. I am still of the opinion that this is a viable alternative, but in efforts to try to get my water quality under control, I have been trying something new. I have been siphoning about 2 gallons out of the tank into a bucket, then pumping that 2 gallons of water from the plant reservoir back into the fish tank. Then again siphoning out 2 gallons into a bucket, and pumping 2 gallons back in from the other Emily plant reservoir into the fish tank. If my basic math is right, that should be a 75% water replacement in the fish tank… The only way that this isn’t WAAAY to hard on the fish is that the water is coming from their tank into the plant side in the first place, so it isn’t a “new water shock” issue.

The thing that absolutely floored me was that on Tuesday of last week, my tank was really heavy/toxic with nutrients, when I performed the above exchange – so the water that I put into the plant reservoir was maxed high in nutrients, (high in ammonia and nitrite), and 2 days later, it was at nearly zero in the levels. The plants had cleaned the water completely in just 48 hours. In that time, it had gone through the entire cycle of ammonia breaking down into nitrite and then further breaking down into nitrate, and all of this being absorbed by the plant for food. At the end of the cycle, there was only a trace amount of nitrate left that the plants hadn’t used yet – and this is the “least” toxic to the fish.

It’s one thing to know that these processes work – it is another to have them definitively shown to work that fast. Way cool.

So… on a sad note – speaking of processes working overly fast (not to mention karma of my last post title)… I was out of town this weekend (Happy pet/house sitting with absolutely fun set of 2 Labradors and 4 cats), and my fish had to be left without supervision. They had enough food to get through the first day, and my research indicates that they can go short periods without food – so I was fairly confident that they would get through the weekend okay. In future thinking – I kind of wanted to know that this was possible for my general life planning, so it was also kind of a mini-experiment.

Well, my tank chose this moment to fully go through the nutrient cycle and clarify the water, something that I have been hoping would happen, but it is a rapid chemical change that is healthiest for me to be around for… Chemically, this means that all of their ammonia and nitrites were converted to nitrates, and because we are talking a small tank – it became very toxic for them in an overload of nitrates. I lost three fish when I was home that afternoon, and another four before the day was done. I (of course) have changed out the water once, and will be doing so again to get the levels safe again, but a sad day. I am hoping that I have guessed the kill reason, and that I’m not dealing with an even more serious issue, but as of the next day, they had stopped dying, so I’m moderately certain it was the toxic stress rather than other issues.

Silver lining, the tank is now crystal clear, so at least I know that it is possible to have that, which has great implications for long term happiness of fish viewing. And those that made it are (mostly) still growing right along and getting big.

Now, back to work transplanting seedlings, as I just planted about 30 new plants to take over for some of my lettuce that has run it’s course. Below is a fish video of those fish that survived. Moment of silence for those that didn’t…

Categories: Aquaponics

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