Finally, I have completed an upgrade to the fog delivery system in the cool vivarium. This new system is delivering the fog horizontally, cascading down about two thirds of the back wall and the right side, enveloping the plants mounted there in a cool mist, and filling the whole vivarium with fog in about 3-4 minutes. I have to turn the fans off while operating the humidifier, otherwise they just smash the fog to bits, but this is not a problem, I just had to dial in the timers properly.
The old system just blew in fog straight into the vivarium via a pipe connected to the humidifier on the right side. Although it would fill the vivarium with fog in a few minutes (with fans off) it has not created the atypical cloud forest “fog cloud” that I wanted to recreate. Until now I have controlled the humidifier with a humidistat, and it has worked fine for just raising the relative humidity in the viv. when needed. And by stabilizing the RH above 80% I have successfully coaxed several stubborn Dracula to bloom… chimaera, deniseana, sodiroi, erythrochaete, barrowii and my fantastic Dracula rezekiana has been blooming non-stop for over a year now. But I have a handful more that has tried to bloom all summer, but the buds abort about half way every time – and it is sooo frustrating!! So, I still think it is humidity related. Raising the RH got me about half way there… so I am hoping that creating a cloud of fog for a couple of hours in the morning and also in the afternoon, coinciding with the daily rain cycle might do the trick. Trying to mimic the actual conditions in-situ.
So, I designed a new fog delivery system, with very simple tools. All I did was to drill a bunch of holes into a PVC pipe, attached it to the fog chimney and attached it horizontally across the back and the right side wall, the wet side of the vivarium, capping the end with a piece of cork. I just attached L-brackets with zipties to the EpiWeb wall and then attached the pipe to that with the use of some more zipties. Zipties… love that stuff, next to duct tape it has to be one of the best inventions ever. The amateur vivarium builders’ best friend.
The old humidifier had just stopped working, but thankfully it was under warranty so they sent me a replacement for free. I actually got a different brand all together since they no longer carry the old model. Just as good, I have actually burned out three units this year alone… no doubt a crappy design. This new humidifier is a “Wilfa HU-6” ultrasonic with an option for either hot or cold steam (I will run it cold of course) with a capacity of up to 300 ml/hour and the water tank holds 6 liters. So 1 liter larger tank than the old one, nice. Let’s hope the darn thing lasts longer than 6 months…
For the first evaluation week I will run the morning rain for a good soaking (one minute each) at 7:00 and 7:30, and keep the fog going 15 minutes on, 15 minutes off for two hours until 9:00. Then I will keep it dry during the day (I might have to add on a fog session here to keep RH up, we’ll see) until 17:00 and 17:30 when I will run the afternoon rain (one minute each). At 20:00 the fog turns back on and runs for two hours until a quick night shower (30 sec.) at 22.00. After one week I will evaluate how it is working and adjust my timers if needed.
The second video shows the vivarium after the fog has been on for about 3 minutes, and then I turn on the rain system.