About that lone Lambchop Rasbora
OK, so that lone Lambchop Rasbora was included by accident. What are you gonna do? Just watch what happens next...Initially, it seemed as if he was just falling in line with the school of Neons. But then, after a few hours, a hilarious pattern emerged: the Rasbora falls in with the school for a while and then wanders off on his own - after all, he's a breed apart. So he explores the tank on his own, that is... until he sees a Neon that became separated from the school, and like a shepherd dog, he starts chasing him, and he continues to chase the Neons until the school is together again, and then for a while he swims with the school, until he is satisfied, and the pattern repeats itself. It will be very interesting to watch if this continues.
For now, I do not want to add more fish until I have a firm handle on the changes in water quality again, though considering my heavy plant growth, I think the new fish will barely move the needle on nitrates, but I also think it will take one or two months before I can tell for sure. I am continuing to take my time to find the right balance between fish and plants.
Hanna Instruments pH tester
Then it was time to turn to the mysteries of pH, that all important parameter, or so it seems. By the way, many smart pros in the field warn against an obsessive focus on pH, other parameters are at least equally important. As per usual, the some of the best source of information are the sections on water quality on the American Aquarium Products site: Nitrogen Cycle, Redox Potential, and Carbonate Hardness (KH) - the point being that if you lose sight of the KH parameter, you are asking for pH instability.
Like most aquarists, I had forever been using the API water test kits for everything, including pH. Amazingly, I had been involved in some technology pertaining to drinking water, and had a set of electronic testers for that reason. Originally, I had kept them at my office, but when I brought them home, I forgot about them until recently, as I became deeply interested in aquarium water quality. My Hanna Instruments ORP and TDS meters were still in good working order, but my pH probe proved unreliable (they had all been purchased in 1999). Quite an amazing outcome, actually. I bought a new Hanna pH probe through American Aquarium Products (Hanna InstrumentsChecker (R) Plus pH Tester - HI98100). It has +/- 0.2 pH accuracy, and automatic calibration. After carefully calibrating it, I began to find that the API pH test (with the drops, I already did not like the strips...) is reasonably unreliable, but the greater accuracy of the HI98100 is worth it, because it provides a more precise and unambiguous reading. I am not saying the API test is unreliable, but it can be harder to read, however, you must be aware that the PH tester needs to be calibrated regularly, and for aquarium work the only calibration that matters is with the pH 7.0 reference liquid. You should do the calibration every time if you only use the pH probe irregularly, but then of course if you have multiple tanks that's still more convenient, and more accurate. If you test daily, Hanna recommends calibrating the tester once or twice a week. Sometimes I do have episode where I'm testing the water daily.
With three tanks, already the convenience of the electronic tester is a significant time saver, and the extra accuracy is a bonus, but I will be monitoring very carefully how all various measurements validate and reinforce my newly accurate pH readings, and to be sure I will periodically recalibrate my pH Checker, but I am sold on this product for any serious aquarist.
Hydor CO2 kit
A good reference chart on KH and pH is the one on Think Fish, here. The bottom line is, for good CO2 levels in a typical freshwater tank, your KH should be between 3.5 and 10 dH, or between 50 and 200 ppm, which reinforces what I said above about not focusing on a single parameter. Now depending on the level of lighting, you may need some CO2 injection, for the plants otherwise may not get sufficient CO2.
In my quest for CO2 on a budget, I scooped up a Hydor CO2 Green NRG Advanced kit, which I would not recommend, because it is discontinued by the manufacturer. I only found that out after I bought it. If you can still find it, they're usually cheap, but you're buying a dead-end product, for which you can get no support. I should have checked the Hydor site first, and I would have realized that the product was orphaned, but... hindsight is always 20/20.
Having said that, for doing CO2 on a budget, the thing actually works sort of OK. I am quite a Hydor fan, so I can only hope some day they would come out with a new and improved version of this design. So far, the main problem I found with it is that it takes some effort to adjust it right, and the valve does tend to drift, so you need to check your bubbles once in a while. You can find a host of YouTube videos on this piece of equipment, such as this one, it's a nifty design, but don't mount it vertically like this video shows... it will work better horizontally, as shown here.
Besides the adjustment problem I've experienced, the fact is that it does not have a solenoid valve, which in and of itself would cost nearly as much as what I've paid for the whole system. I did put it on a timer however, so at night the CO2 (12 bubbles per minute), just bubbles up and escapes, whereas during the day the diffuser runs and that works really well, so the CO2 is really absorbed into the water very well. It is a nifty system that uses a little motor, similar to Hydor's Bubble Maker, for oxygenating your tank. Again, since it has been out of production for 8 years already, you cannot get any replacement parts for it any more, and it is only a matter of time until I will have to get a serious CO2 system. Economics also plays into it, for even on my 29 Gallon tank, I am now going through on 74g CO2 cartridge in 4-6 weeks, and they cost $10 each, where as a five pound CO2 tank would probably last a year or more on such a small tank, particularly with a solenoid valve, so it would be shut off at night, and a single charge costs me $20 around where I live.
CO2 wish list
I've been speccing CO2 systems for a while, and my guess is that my next move would be the Complete Ultimate CO2 System form Aquariumplants.com, here. That system truly looks awesome. The truth is a completely automated CO2 system is the way to go, especially for a larger tank with serious plants. Number one, by shutting it off at night, besides saving some CO2, you are reducing the risk of over supplying CO2, which is not good for the occupants. Your plants exhale CO2 at night, while they inhale CO2 by day. I used to have such a system when I ran a 125 Gallon tank for nearly 20 years, and it was quite the thing, to be able to simply regulate your pH automatically with such a system, rather than counting bubbles, as you have to do with any system that you need to regulate manually. (I do it once a week with my Hydor system, to make sure...)
Conclusion
Once you get serious about plants, you have the low-tech way, in which you balance fish and plant population, because fish waste is plant food. Diana Walstad is the big proponent of that model currently, but it is a very traditional approach, and all my earliest tanks in my childhood days were based on that principle. You should see this review by Dustin, and this interview with Diana Walstad by Aquarimax.
If you are open to go hi-tech, with lots of lighting and CO2 injection, you may be able to get by with a manually regulated CO2 system in smaller tanks, and there are numerous options on the market. Generally speaking, the cheaper they are, the more work they require. Once you get into larger tanks, an automated CO2 system with a pH-probe that controls the CO2 diffusion is the way to go. At that level the idea that CO2 injection is extra work no longer applies. It will actually reduce the work, though you will have to trim your plants more often.
