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A Reef Legend and a Reef Robot: How the Alkatronic Helped Me Achieve Stable Alkalinity After 30 Of Years Trying

A Reef Legend and a Reef Robot: How the Alkatronic Helped Me Achieve Stable Alkalinity After 30 Of Years Trying

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If you ask most hobbyists what the single most important parameter to measure is, most will say alkalinity (which is also called a buffer).

If you then ask them to explain what it is and why it is important, most will give you a blank stare or say it is necessary as corals use it for their skeletons. I agree that alkalinity is the most important parameter to measure. For me, it gives a quick snapshot of how the tank is doing overall. It is also the one parameter I least want to fluctuate widely in a given day or over a short time span.

Many hobbyists I speak with are so concerned with this parameter that they measure it constantly, with some measuring it daily and some as often as three times a day. While I am obsessed with this parameter, even when I was really concerned with its level, I still only measured it once a day when I was measuring it via a test kit.

In a nutshell, alkalinity is the capacity of water to resist changes that would make it more acidic. It is related to pH, in that it is a measure of what it would take to reduce a given amount of water to a pH of 4.5. Obviously there is chemistry involved, but I am not going to dwell on that here. It is important in that not only does it provide a measure of how stable the aquarium is, but as mentioned above, it is essential that corals consume “alkalinity” to form their skeletons.

In normal seawater the alkalinity is approximately 7.0 dKH which is 2.5meq/L or 125 ppm Calcium carbonate equivalents. Calcium carbonate can be considered the same as alkalinity as CACo3 makes up the majority of the ions in calcium carbonate in seawater. Most reef keepers, especially hobbyists with heavily stocked SPS tanks, keep their alkalinity higher than normal seawater in the range of 7-11 dKH, 2.5- 4 meq.

This is done in order to keep alkalinity from being the limiting factor in the corals’ growth. Some even keep the levels higher than this, which is okay. But at higher levels there is the possibility that it may precipitate out calcium. Care needs to be taken at these higher levels.

It should also be noted that at higher pH levels, above 8.2, coral calcification and growth will be higher than is the case at lower pH levels. When this is occurring, the alkalinity can be depleted rapidly. However, even at lower pH levels alkalinity can be depleted quickly and this is why this measure needs to be monitored closely.

In several of my friend's aquariums where SPS corals are growing rapidly, if their means for adding alkalinity malfunctions, drops of 2 dKH have been noted. Drops like this, as well as rapid increases of this magnitude, have been shown to be stressful to SPS corals. In my own tanks, as well as those of my friends when these kinds of rapid changes have occurred, we have seen an increase in slow tissue necrosis (STN). This malady is manifested by bleaching in SPS corals typically starting at the base of the coral or frag and then slowly progressing up the coral.

This is why it is so essential to keep alkalinity levels stable and this can only be done (for the most part) with regular testing.

But let’s face it. Testing is neither sexy nor fun.

Most of us typically only do it when we are seeing problems, which in the case of alkalinity, is often too late. In addition, with most testing, there is a chance for user error and a degree of variability between test kits. There is also the question of how often testing needs to be done. There is also variability caused by what time of day the alkalinity tests are done. If tests are done at different times each day, the measurements found can be significantly different.

When Focustronic released the Alkatronic alkalinity controller, I got one of the first units. I got it because despite my best intentions to monitor alkalinity frequently, I am often traveling or busy with my family or life. So at best, my measuring of alkalinity was more irregular than I wanted.

Even though I always logged the test results into my phone to monitor and track for changes, my overall log was haphazard with lots of variation between numbers and the times when tests were performed.

I am not Mr. Technology. So I was surprised by how easy it was to set up the Alkatronic. I removed everything from the box, watched the YouTube video about how to set it up, and got it all together in only 30 minutes. The best part is it worked! I was impressed. I've experimented with other aquarium solutions that left me feeling as if a programming degree should be listed as a prerequisite to getting the thing working.

I like that I can set up the Alkatronic to take the alkalinity measurements as often as I like. I began by testing every 4 hours. I wanted to see how much the alkalinity varied in very short time spans, especially during the nighttime. I set ranges for the high and low alkalinity values so the Alkatronic me alerts if the water chemistry drifts outside my safe zone.

Also, if the value differed markedly from the value I got on a reliable test, it could be adjusted on the app. And lastly, I liked that it could be set so that if the value came in low the Alkatronic could add small amounts of buffer to keep things stable.

It may have a front door, but Focustronic isn't trying to hide anything from users. There's nothing mysterious behind door number one. No secret probes or magic spells. It's just good old-fashioned titration testing—the same type of tests we're already performing manually—performed by a machine to remove the human variable from the equation.

The Alkatronic is easy to set up and understand. It's also surprisingly easy to maintain.

The three peristaltic pumps that run the Alkatronic require calibration every 2 months. It's easy to do and takes only 10 minutes. You won't forget, either, because the Alkatronic will send alerts to remind you of your duty. Everything 3 months the pH probe will need calibrating. This chore also takes just 10 minutes. The amount of reagent you mixed in the previous match and how often you test determine when to mix-up the next batch, which for me is quarterly. If words like peristaltic, calibration, and reagent are new to your aquarium vocabulary, this explanation may have been difficult to follow. But it's not. Nor is it time-consuming.

I was logging my readings even before I got the Alkatronic. The difference is now I can easily see how the levels vary over a week's time. This knowledge is what's allowed me to maintain the alkalinity at a level of precision I've always sought but was never able to achieve. This has proven to be essential for the long-term health of my SPS corals.

Since it has been set up and the consistency of both the Alkatronic and my means for maintaining alkalinity have been demonstrated measurements are now only taken every 6 hours. I only increase the frequency of testing when I change an aspect of the tank and want to see if it affects alkalinity.

Is this unit perfect and have I had problems with it? No and yes. If the unit is not regularly calibrated the values can drift and when mixing up the new reagent it needs to be done precisely, otherwise the values can be off. Also, from time to time it can lock up or give a reading on the screen that is not easily understood. In these instances, I have contacted customer support and fortunately they were able to explain and correct the issue within 24 hours. I currently run the Alkatronic with a dosing system, but I ran it with a calcium reactor in the past. With both systems from time to time there were issues with alkalinity levels either getting too low or too high due to issues with the dosing equipment. In all cases, my looking at the Alkatronic allowed me to see that these problems were beginning to occur and allowed me to intervene before they became problematic. I use most electronics to measure things rather than measure and adjust things, so I do not use an Apex or Trident. I have used a KH Guardian and the Alkatronic is is significantly more reliable than that device. And for me when I decided to purchase an Alkalinity monitor I wanted one where reliability and stability were tantamount.

Overall I very much like this device as it does what I need and it does so reliably. After the initial purchase, the cost for maintaining it is mainly purchasing the reagent, which runs me approximately $100 per year and will be less as I have reduced the frequency of testing.

I also like the device as it uses technology that I understand and that is reliable. Because of how well it works, I am very much looking forward to the release of the Mastertronic, which promises to measure the other parameters that I measure regularly. I’m hoping it will also chart these parameters as well so that I can then compare these parameters in real-time and assess how they interact.

I also like the unit as I can look at the alkalinity any time I want via the app on my phone. While I can’t adjust levels via that app yet, it does allow me to communicate with the people who are taking care of my tank when I am away and make the adjustments as needed.

I got the Alkatronic with the goal of improving the stability of the alkalinity in my reef tank. Mission accomplished.

It also helped me make adjustments slowly when things are off. In the past, I made adjustments too quickly and created bigger problems. The machine also reminded me of the skill every reef hobbyist preaches, but has difficulty practicing: patience.