Best heaters to use with controller?

[iwishtofish]

My two 300w heaters aren't keeping up! I need to upgrade, and I'd like to use a controller (probably RKL1). Need advice!!

[bamf25]

How much water you have? I am using 400w (2 x 200w ehiems) in a system with about 130g total. It does great for me. The big variable however is what is you abmient temp in your house? Do you have A/C? What kind of lighting are you using?

[iwishtofish]

Originally Posted by bamf25

How much water you have? I am using 400w (2 x 200w ehiems) in a system with about 130g total. It does great for me. The big variable however is what is you abmient temp in your house? Do you have A/C? What kind of lighting are you using?

I have a 75g tank with a 40b sump. I can't figure things out. I have a 300w Eheim Jager set high enough that it never turns off, and a Finnex 300w "digital" set to 80 degrees. There is central A/C in the house, but the basement (where the tank is) is controlled by the thermostat on the main floor above. The basement temperature can vary a couple degrees on either side of the thermostat setting upstairs. Sometimes when the basement air temperature drops to 67, the tank temp nears 77 (sometimes cooler). Sometimes when the A/C doesn't run as often because the day is a little cooler, the basement gets warmer than the upstairs, and the tank with lights on nears 80 degrees.

The tank is a peninsula-style open-top with a LOT of surface agitation. The stand is currently open. The lights are a 6-bulb, 36" Tek T5 fixture, currently well above the water since I have no corals.

I'd love more ideas and advice!

[sjm817]

What do you use for a return pump?

[tozzi]

That should b plenty for your water amount. And btw 77 degrees is fine for a reef. From 76-82 is safe imo

[iwishtofish]

Originally Posted by sjm817

What do you use for a return pump?

Scott, it's a Mag 9.5, but it's probably only about 300-350 gph at the tank due to reactors, fuge, etc.

Originally Posted by tozzi

That should b plenty for your water amount. And btw 77 degrees is fine for a reef. From 76-82 is safe imo

Yes, but is the 2 - or maybe even sometimes 3 - degrees variation good to have over the course of a day?

[sjm817]

Just checking that you are using a water cooled pump which helps with the heating. You are SURE both of those heaters are working? They are hot to the touch most of the time?

[iwishtofish]

Originally Posted by sjm817

Just checking that you are using a water cooled pump which helps with the heating. You are SURE both of those heaters are working? They are hot to the touch most of the time?

The tank receives passive heat from the Mag 9.5, the skimmer pump, a mini-jet, a Koralia 4, and a Koralia Magnum 7. I know I have seen heat coming off the Eheim Jager heater when the light is on, and I remember the Finnex heater feeling hot when I was moving it.

All I can think of to do is to get a controller with a temp probe to put in the DT, crank both heaters to the max, and give that a try. The Finnex is supposed to have an electronic memory to keep it at the proper setting when power is lost and resumed, but I'm not sure I trust that.

[sjm817]

Doesn't sound right. 2 x 300W should have no problem keeping that system up to temp. A controller wont fix that if they are always on and cant keep up.

[iwishtofish]

Originally Posted by sjm817

Doesn't sound right. 2 x 300W should have no problem keeping that system up to temp. A controller wont fix that if they are always on and cant keep up.

I know. I'm certain the Eheim Jager is on all the time because of the light, and the Finnex is set to 80. Maybe the Finnex isn't accurate, although the tank gets hotter than I want when the room temperature rises just a few degrees.

My sump before the second heater:



How the two heaters are set up now:



The refugium baffle is really tall, and spills over a good ways into the return compartment.

[BeanAnimal]

How many gallons do you evaporate a day? You get a little over 8,000 BTUs of cooling per gallon of seawater evaporated. Lets call your total system volume 100 gallons. You have 850 pounds of water, so if you pull 850 BTUs from the tank, you get a drop of 1 degree F. 1 gallon of evaporation equates to about 9 degrees of pulldown in your system that the heaters have to make up.

So if you evaporate 2 gallons per day that is about 16,000 BTUs lost or about 666 BTU/hr.

If you evaporate 5 gallons per day that is about 40,000 BTUs lost or about 1666 BTUs per hour.

You have 600W worth of heaters, capable of 2049 BTU/hr. so even at an evaporation rate of 5 gallons per day and other smaller loses (convection, conduction, radiation) your heaters should be able to keep up.

Secondly, you really should be running those heaters from a dedicated controller such as a Ranco. I would NOT run my heaters without a controller and would opt for a dedicated controller and NOT a reef controller.

[iwishtofish]

Originally Posted by BeanAnimal

How many gallons do you evaporate a day? You get a little over 8,000 BTUs of cooling per gallon of seawater evaporated. Lets call your total system volume 100 gallons. You have 850 pounds of water, so if you pull 850 BTUs from the tank, you get a drop of 1 degree F. 1 gallon of evaporation equates to about 9 degrees of pulldown in your system that the heaters have to make up.

So if you evaporate 2 gallons per day that is about 16,000 BTUs lost or about 666 BTU/hr.

If you evaporate 5 gallons per day that is about 40,000 BTUs lost or about 1666 BTUs per hour.

You have 600W worth of heaters, capable of 2049 BTU/hr. so even at an evaporation rate of 5 gallons per day and other smaller loses (convection, conduction, radiation) your heaters should be able to keep up.

Secondly, you really should be running those heaters from a dedicated controller such as a Ranco. I would NOT run my heaters without a controller and would opt for a dedicated controller and NOT a reef controller.

Thanks for weighing in, BeanAnimal. I believe I evaporate 2 or more gallons/day.

Where can I find a Ranco controller? I take it the temp probe sits in the DT?

Do you think it possible that the fact the room can get quite cool and and there is much air flow all around the tank and sump could contribute to my tank not staying up to temp? Should I invest in better/larger heaters to put on the controller? I was thinking of using the RKL so I could control a cooling fan, as well, if the temp rises when the room gets hot.

[geaux xman]

if both heaters(600w) are on for an extended amount of time, i think the temp would easily exceed 80degrees in a 100g net tank.

i have a 500w titanium and when i was cycling, i kept it at about 85 degrees and it had no problems maintaining that. this is a 200g+ net system. without the heater, my water temp was sub 70 degrees.

[iwishtofish]

Originally Posted by geaux xman

if both heaters(600w) are on for an extended amount of time, i think the temp would easily exceed 80degrees in a 100g net tank.

i have a 500w titanium and when i was cycling, i kept it at about 85 degrees and it had no problems maintaining that. this is a 200g+ net system. without the heater, my water temp was sub 70 degrees.

I have no explanation! It seems when I turn the Ehiem Jager up higher, my tank can get too warm if the room is warmer. My best guess is the combination of evaporative cooling, lower flow, and open design must be powerful factors in the tank retaining heat. ????

I want to try the controller with the heaters, but I'm not sure I trust the Finnex to retain it's temp setting (because it has a digital thermostat vs a mechanical one). Can you recommend good heaters to use with a controller?

[BeanAnimal]

http://beananimal.com/articles/aquar...-to-know!.aspx

Take a look at the link to my website, where I go into detail about the heaters and controllers. It is easier than trying to explain it over and over

[sjm817]

The Eheims are good. The Finnex is not. The built in temp controller is junk and resets itself to 80 (which can be very far from 80) when power is lost. You want the heaters set just a bit higher than the external controllers temp.

[BeanAnimal]

Did not even realize that about the finnex! I knew they were utter junk, but wow!

[iwishtofish]

Originally Posted by BeanAnimal

Did not even realize that about the finnex! I knew they were utter junk, but wow!

Well, supposedly this heater has a memory to retain the setting, but I'd feel more comfortable not having to worry about it.

[iwishtofish]

Is this the correct Ranco? I thought I had read something about a 2-stage - is that to control two devices, such as heaters and cooling devices?

http://www.amazon.com/Ranco-ETC-2110...4343794&sr=8-7

[sjm817]

Originally Posted by iwishtofish

Well, supposedly this heater has a memory to retain the setting, but I'd feel more comfortable not having to worry about it.

Maybe they fixed that since the last time I used one.

[iwishtofish]

Originally Posted by sjm817

Maybe they fixed that since the last time I used one.

Great, haha. I tried to "calibrate" the dial on my Eheim Jager, but the indicator needle wouldn't turn all the way to the corresponding temperature. So now I have no idea where it is set, just that it is set high enough that it is always on.

Ok, going to research heaters more, find the correct Ranco controller, and also the correct fan to come on with the lighting (yet more evaporation!).

I have wasted so much money on heaters - my Via Aqua titanium died right after I set up the tank.