Hi Shawn - Great post. I couldn't help but be reminded of one of my own experiences regarding the battle with thermal control. I figured I'd offer it up for your and others' consideration.
About 3 years ago I installed a 240 gallon reef aquarium for a client. 240G does not seem large but there were a number of anomalous factors to consider but the two most important for the point of this conversation are:
- He wanted all of the filtration located in the basement in a mechanical room. This resulted in a large Reeflo 8400 pressure pump (to address approx, 16 ft of vertical head); and
- The house was large enough to constitute what turned out to be a light commercial electrical system, but was unfortunately not equipped with a central surge suppression system. And to add to this point, the house was located in an exclusive neighbourhood surrounded by farms... which means that 'clean' hydro is not guaranteed by the local utility.
The latter point is only important to further enlighten the following context.
The Context:
Within the first year of this installation, I'd gone through three 1HP chillers (not to mention a few other electrical components), before putting my finger on the dirty hydro realization. Because of the configuration of this aquarium system (i.e. everything in the basement), as well as the extensive lighting system (5x 250W HQIs - 2x 96W PCs), there was a huge emphasis on cooling.
At the time I could not persuade my client to spend the additional $2K on the Aquatronica system that would have provided early warning... so all of the above combined to result in 3 terrible phone calls from my client stating that "...the tank is 95 degF; I'm thowing ice cubes into the aquarium; and all of the coral and critters are dead; we only have a few fish left alive...." In a nutshell, on three separate occasions, three large power-sucking, 1HP chillers which worked [let's say] 80% of the time to maintain 78 degF, suddenly stopped functioning, and within the course of a night, allowed the aquarium temperature to rise up to 95 def F.... this happened three times in one year.
Needless to say at this point, the I could not trust a single chiller solution, since as can be seen - it proved to be an all or nothing gamble. My client was no longer willing to invest thousands of $$$ in a project that seems to be mysteriously, and anomalously revisiting disaster.... and I was on the hunt for a better solution, as I didn't want to deal with this type of customer/client devastation any longer, with this or any other projects.
The solution:
About 12 years before this whole ordeal, I was in my second or third year completing my architectural degree, in a class, learning about cooling towers. Some of you may be aware, but here is the key point about cooling towers. They rely on the phenomenon of evaporative cooling (which I learned at that time) basically means that the phase change from liquid to gas requires heat - so what a cooling tower does is spread water over a metal lattice to thin it out, while fanning air counter-current (upwardly) through that same lattice. The water is encouraged to evaporate thereby steeling the heat from the water (left behind) to accomplish the phase change to vapour. Of course my first thought at that time was 'I can make this work on aquariums' - thinking of goldfish at that time to be honest - I wasn't into reefs at all.
(once again I apologize to those of you who already knew the details of evaporative cooling)
Nonetheless - as you can probably see, this epiphany of mine was shelved for approx. 12 years, until the point in time that I was at the end of my leash with chiller and hydro related disappointments.
I then proceeded to retrofit an existing bio-tower with an extension (taller); a couple of air channels (to direct air down to the bottom); a vented top; and two $65 [5"] computer fans (to feed air through the two channels).
When I finally got everything hooked up correctly, the temperature dropped from 95F to 74F in the winter. In the summer months when the mechanical room was naturally more humid, the evaporative capacity diminished to the extent that the temperature hovered around 78-80F. Since the system relied only on two $65 computer fans, I was no longer contending with the replacement of a $2,000 chiller after the warranty was up; and there was now [in place] a very economical solution of redundancy. The system has been in place for almost three years now, and I have never had another reef-cooking incident... thankfully! (though I did have one close call when a lightening storm tripped the GFI the fans were plugged into, but that only required a reset - this of course only qualified the dirty hydro finding)
Oh, and BTW - after designing my own sorta DIY solution I discovered that Deltec has a commercial solution that operates on the same principle of evaporative cooling... their eco-coolers.
Cautionary Notes:
- My first evaporative cooling system relied on a modified bio-tower which is okay for fish-only and even lps/soft coral reefs; a sps system would then have to contend with a now super-charged bio-tower, and the resulting production of nitrates (which is entirely controllable via carbon-dosing btw). I've addressed this issue by designing alternate ways of thinning out the water toward ease of evaporation.... i.e. find some way to spray the water through the cooling chamber as opposed to trickling it over any media - in other words, minus the substrate for the nitrifying bacteria to live; and
- most importantly... find a way to dispose of the generated humidity or you will (in most houses) begin to find mould in areas of moderate to no air circulation. This actually goes for all types of evaporative cooling including fanning your sump or display tank water surface. I actually had three computer fans blowing the surface of a large (600g) freshwater installation, and my client found mould cropping up in other areas of the basement. needless to say we put glass tops on the aquarium and the water temperature went back up to 86F (from 76 or so when the fans were in place). Once again there is a solution; and it is simply this... if you employ a proper strategy of evaporative cooling, i.e. with a reactor (not fanning surface water), you must treat your installation in a manner similar to a shower; dryer; or even a fireplace installation - send the unwanted stuff (humidity) straight outside... if you're going to invest in an aquarium in which cooling is a primary requirement; in my findings evaporative cooling is least energy intensive and more reliable. If this is something you would consider getting into, then by all means pop a 4" vent through your wall and avoid any chance of mould production inside your house.
Anyway - sorry about the long post - I just couldn't help reflecting on my own past woes when reading through Shawn's post. I figured that my eventual solution and learnings were worth sharing; and most appropriately worth saving others similar heartaches. Hope it was informative.:wave:
Regards,
Sheldon
. I look forward to your experience with this beautful angel as they can have different tastes in food and personalities.
