I disagree with everything you just said.^^^
I am not picking on you, but you appear to have changed or missed the meaning of almost everything I posted. Let's look a little deeper and see if we can expand on some of the things I posted. The dynamics and dangers of something as simple as a heater in an aquarium are often overlooked or misunderstood. Countless systems are damages or destroyed because best practice is not employed.
-We are not talking about putting them in plain sight.
I did not say you were but offered my opinion on the matter. However, "best kept in the aquarium"
could mean
in the display OR
in the overflow. I offered my opinion on the first point (in the display) and factual information regarding why the second point (in the overflow) may pose a problem. See below:
-In an overflow like we are talking, even when you do a water change out of the DT the level in the box stays the same.
Please read my post again. "Heaters in an overflow can run dry
(of course depending on the style of overflow). I did not give an absolute, I offered a warning. I.E. not ALL OVERFLOW STYLES stay FLOODED or maintain a SAFE level for heater operation.
Remember, everybody following along may not be on the same page. What appears as harmless advice may in fact get somebody in trouble if they don't fully understand the context of the advice.
-Heaters do not, as you say "ALWAYS" have to be ran from a controller.
You left out a word. I said "
should ALWAYS", inferring BEST PRACTICE. Leaving out words changes meaning and you have disagreed with something I did not infer.
Granted that would be preferable
That is what "
should ALWAYS" STRONGLY denotes
but I look at my tanks everyday and can tell when a thermostat is stuck on. Therefore I've always saved my hundred dollars that the controller would have cost.
While checking your system components daily is certainly a VERY GOOD idea, doing so does not provide the same level of safety that a quality temperature controller does. What happens if you DON'T make it home for a day? Two days?, etc. For any set of criteria, there is an acceptable level of risk and/or a point of diminishing returns with regard to complexity vs cost vs safety. Most folks make poor or uninformed choices with regard to aquarium heaters because they simply do not fully understand or take the time to consider the criteria. The result is a false sense of security based on their percieced (lack of) risk. The comfort creates a false point of diminished returns and next thing you know, $3,000 worth of livestock and 5 years of work are destroyed in hours by a $20 heater. Sadly, in almost all of the cases, a reliable controller and application of best practice (as outlined above) would have prevented the loss.
That is, while you may have "saved $100" a simple overheating event caused by a stuck thermostat (something that has nearly a 100% chance of happening over the life of the heater) can easily do thousands of dollars of aggregate damage to your livestock and begs the question: Did you really save $100?
-The location of the temp. probe should'nt matter at all because of the flow rate, and putting it downstream is just as pointless.
I did not say to put it downstream, I said to place the probe upstream of the heaters. It certainly does make a difference in the way the heaters cycles and the temperature stability of the tank. The larger the heat load (loss) on the system, the more important this becomes. The lower the turnover through the heater area, the more important this becomes. This is basic physics (thermodynamics) at work and one of the fundamentals of process control.
The water that passes by the temp. probe is always in a different part of the tank/system.
If the probe and heater are in DIFFERENT compartments of the system (separated by baffles or by the sump/display plumbing, etc) then a pump failure (or forgetting to turn the return pump back on after feeding or maintenance) can result in calls for heat (or calls to turn off heat) being erroneous.
Example:
Temp probe in the INTAKE compartment of the sump, heater in the return compartment. You turn the pump off to feed the fish and go eat dinner. The room is cold, so the sump loses temperature. The probe calls for heat and the heater kicks on. It begins to heat the water in the RETURN compartment, but the probe has no clue because it is sitting on the other side of a baffle or two. The water in the RETURN compartment nears boiling, as you remember to turn on the pump. You turn the pump on and send 5 gallons of scalding water into the display tank.
That is one of MANY scenarios that illustrate why we don't put the heaters in different compartments with relation to the sensing probe. There are steps that can be taken to minimize the risk (using the integrated thermostats as fail-safes) but the best practice still holds true and (as mentioned) there are numerous other scenarious to account for.
-If you want to put the heater in a sump compartment, again, all you have to do is observe your tank daily and top-off evap. and the running dry problem should never arise.
Again, what happens while you are sleeping, the ato fails, you are caught late at the office, etc.?
With a little bit of common sense and planning, almost ALL heater related disasters can be totaly avoided. Ignoring best practice significantly increases the chances of a heater caused or related aquarium disaster and that is why such events or so extremely common.
If you want to delve deeper into this topic and "best practices" that can help to ensure your life support system stays safe and fairly fail-safe then you can take a look at the article I wrote regarding the topic. I did so, because this subject comes up VERY often here at RC.
http://beananimal.com/articles/aquarium-heaters-what-you-need-to-know!.aspx
Happy Reefing
