Since the addition of the Profilux controller I've been monitoring the pH cycle of the tank quite closely. I must admit that I just love this kind of thing, it's the scientist in me. I've noticed that the minimum value was lower when there were two of us working in the same room as the tank than when it was just me or even when there was no one in the room at all. When there were two of us working in there the pH would drop to below 8.0. I thus began thinking about adding a CO2 scrubber to my protein skimmer to see what difference it would make to the pH cycle.
There are a couple of scrubber options on the market (that I know of) and after brief consideration I decided to try the new ATI Carbo EX filter since I have used their ICP test recently and the price seemed quite reasonable. Connection to my skimmer was easy and I have it situated in the cupboard alongside the tank (next to my RO resevoir). It measures just under 21cm high and 10cm diameter for anybody interested in the dimensions.
As soon as the scrubber was connected I noticed that the tank pH began to rise, so it certainly appeared to be working. Frankly, I'm amazed that just breathing in the same room can have such an effect on the pH of a tank. I have drawn up a graph from two typical daily 24hr pH cycles, taken from 8am in the morning (when the lights switch on) to 8am the following morning. The green line shows data from the 15th of June (6 days before the fitting of the reactor, we were out of the house for half the day) and the blue line is from the 28th June (6 days after fitting the reactor, I was working in the same room for most of the day).
As you can see the pH before the scrubber fluctuates from a low of 8.03 to a high of 8.16 and with the scubber it cycles between 8.23 and 8.34. Obviously this is data sampled from just 2 days but from from my general observation, the pH is most certainly higher with the scrubber and interestingly the cycle has a slightly narrower maximum and minimum range. Will this have a positive impact on the general health of the tank? That's the important thing, watch this space for updates!
After waiting absolutely ages for delivery I was finally able to set up my shiny new GHL Profilux 4 controller over Easter. The hope is that when the time comes I can monitor the tank whilst I'm away, so less worry for me. At the moment I just have it set up with four probes measuring temperature, pH, redox and conductivity.
There is just 0.1 degree Celsius difference in temperature readings between the digital GHL probe and the Simplyaquaria temperature controller which is pretty good going considering the price difference between the two. I am going to keep the Simplyaquaria controller running as a backup to the GHL, two alarms are better than one in my books. I may actually move the Simplyaquaria probe to the DT so that I have two separate temperature readings to compare.
The conductivity of the tank water measured by the GHL probe was 51.8mS which converts to a specific gravity of 1.0257. My calibrated refractometer measured it to be 1.026, again the values are pretty close which is good. I am happy to know that I've been maintaining a suitable salinity using the refractometer.
I never bothered to purchase a pH test kit this time round so I had no idea what the actual pH readings were going to be. The levels are fluctuating between 8-8.2 or thereabouts, I would like to study the whole 24hr cycle but haven't managed to work out how to access data from the Profilux yet (if indeed it's actually possible to do).
The redox probe is still bedding in, to be honest I'm not really sure what to expect from the readings as I've never used one before. It came with the set so I thought it'd be interesting to set it up and investigate what it can tell me about the tank.
On the livestock front, Charlie the hitchhiking hermit crab is now on borrowed time after his first tank misdemeanor yesterday. He knocked my prize Acropora gomezi frag off the rock in his quest for food. I supposed I should be pleased that he just wanted to graze off the rocks and not eat the coral but still it's annoying. He's really quite big now so I'm sure that he'll cause more trouble in the future if I don't try and catch him now.
I think the T. nudus gobies have spawned again, Hop has been sequestered in the cave for the last two days and Skip won't let him out to feed, so I'm hopeful that there are eggs hidden inside. I hope I actually get to see some fry this time round, pretty please! The Cardinals also appear to be courting but there's been no further release of eggs.
Hi, my name is Lisa and I live in Derby, UK. I am a self-confessed reefaholic!