it goes without saying but i was surprised to find the guppies still huddled near the surface of the tank today. with the cherry barb gone, i figured they'd be swimming around the tank again, however that wasn't the case. so i did what i normally do when faced with an unsolved problem, i went online looking for an answer. a few google searches later i came to the conclusion that maybe there was something wrong with the water. the only things that's changed since a few days ago - when the guppies were still quite active - was the addition of the cherry barb tank mate and the re-introduction of the CO2 injection. turns out a high level of CO2 changes the pH level of the water. i did a pH water test - which is essentially mixing the water with some special droplets that change color - and sure enough, the water was acidic. but how come the tetras didn't seem to be affected? well, tetras actually like acidic water conditions (5.4-7.8 pH). guppies on the other hand like their water more alkaline (basic, 7-8 pH, the same as sea water, which is why sometimes people keep guppies in marine tanks). could this be what's bothering them?
so immediately i disconnected the CO2 intake hose and replaced a gallon of tank water with tap water that'd been sitting out for more than a day. i also ran the test on a few other sources: the hexagon tank i set up yesterday (which isn't amplified with CO2) has a pH of around 7.0 (essentially neutral) while regular tap water had a surprisingly alkaline pH of 7.4. i checked the pH of the minibow throughout the day, and even added a few pinch of baking soda to shift the pH level higher. by evening the guppies were still pretty much hanging out near the top of the tank, but occasionally they'd move down. let's see what happens tomorrow, i'll check the pH and maybe change some more water.
i always knew pH was important but figured these common aquarium fishes would be hardy enough to adapt accordingly. apparently this isn't the case. what this means is i can't inject anymore CO2 into the aquarium for the time being, unless i find some way to do it without decreasing the pH level (or get rid of the guppies and settle for the more acid tolerant tetras). besides pH there's also alkalinity (KH) and the general hardness (GH), but i'll cross those bridges when i get there. having a fish tank isn't just about adding some fish to water, it's a lot more complicated than that, as i'm finding out this entire week. there's all these variables to take into consideration, things like tank size, temperature, pH level, alkalinity, general hardness, phosphate concentration (that's another thing, high levels cause algae growth), lighting, diseases, and whether or not the fish are even compatible with one another. nevertheless, i find it all very entertaining, something to keep me busy during the winter months and beyond.
apart from taking care of my fish drama, i wasn't very productive the rest of this friday. the weather was unseasonably warm again but the overall drabbiness made me stay indoors and not venture out for another run. my one run a week schedule is probably not making much of a dent health-wise. i really don't have any excuses other than pure laziness, since i don't have anything else going on. and since i woke up so late (had a hard time falling asleep last night because of my late night nap) there was only a few hours of daylight before it got dark again. and did i mention this mysterious rash? some of it is due to poison ivy (there's still some mysterious source in the house, probably the desk chair in my bedroom) but also partly due to seasonal dry skin. if it still doesn't clear up by next week i may have to go see a doctor about it, get some prescription strength ointment.
lunch came in the form of a bowl of microwave vegetables with cheese while dinner was just some korean ramen with kimchee. somewhere in the middle i soaked for an hour in the tub, the water was surprisingly hot for a change (sometimes the water can be just lukewarm). i caught the finale of battlestar galactica, the episode setting the stage for another human vs. cyclon battle. the part where baltar returned briefly to galactica as a cyclon envoy was so sweet.
i finished out the night by eliminating 2 more colossi: the giant with the ball legs and bracelet, and the horse that walks on stilts. it took me forever to get to the bracelet giant, i kept on falling off that long staircase into the water and having to swim back to where i started. i must've done that for an hour before i got to the platform where the colossus was. this third beast took 30 more minutes to dispatch and i was deathly afraid of falling off the platform again so i fought tentatively. the stilted horse was a lot easier, no tricks, just had to figure out how to crawl on its back and stab it in the head.