12G nano cube & temp control question


Reefing newb
Hi all.... I've been away from the saltwater fish world for a spell and I'm after 2 years getting into keeping marine fish again. I was given a 12G nano Cube and I noticed it was getting a bit cold (74°) so i bought I small heater for the tank.I was told that a marine tank should be between 78° to 84° but I was wondering for all of you familiar with the nano cube setup if i was to setup the heater in the 3rd chamber where the power head is located so that when the powerhead pumps the heated water out it would evenly distribute the warm water and not to mention i also have bio-balls in there. will it kill the bacteria forming in the Bioballs or in that section of the tank and is there any negative effects to putting there instead of in the main vewing area in the tank? Right now all i have in there are 2 damsels while cyceling but i will be ading coral in the next few months and i wanted to make sure the conditions are right.
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Thanks but those post are from Aquapod Owners complaning of there tank is heating up to much my issue is its cooling down to much to 74 deg I own a JBJ Nano pod with no heating issue. I bought a heater but my question was if i put it in 3rd chamber where the pump gets its water from and its also where i also have Bio-balls. If I installed the heater there to heat the water to drop no more then 78 deg. will it kill the bacteria in that chamber when it begins to heat upthe water. The reason i wanted it in there is so that when it dose heat up it can pump the heated water and evenly distribute it throughout the tank.
Basically you can place the heater anywhere where the ciculation is good and the heater should not be in contact with any other stuff (bio balls, bottom of tank, electrical cord to pumps, etc. as long as you have good water movement around the heater you can place it anywhere you like. also you need to make sure that the heater will not be in a spot that will allow water to get too low. my two cents. good luck. (50 watts should be enough).
Ok... so maybe my idea was not the best in the world. I might be wrong but Last night I added a Neon moon light that i placed inseide the canopy where the lights are wich is shielded by a plastic splash gaurd. Last night I installed the heater in the 3rd chamber as per my previouse post and set the temp @ 79 deg. To my surprise i woke up this morning and my tanks temp per my digital therm. it said my tank was 87.9 deg :frustrat:. After unpluging the heater and turning off the moonlight my tak began to drop in temp. Was the heater in the small 3rd chamber of the nano cube in the back where the pump is the problem? I thought that it would only trigger on if the water temp dropped below 79 deg. Or is the water in the samll chamber of the filter colder then in the main area of the tank that caused it to most likely stay on all night and nearly poched my fish. Would the Neon moonlight contribute to the heat ? Pleae all you Gurus help :bowdown:
If water is moving thru the third chamber at a fairly decent flow then you should be ok.

My other concern is, is the heater completely submerged under water? This is very important and most bio ball chambers aren't under water....

Let us know.
Thanks for the reply brandon. AHHH no. I left the temp knob slightly overwater level, its just the dail out of the water. Could that be the issue since i didn't fully submerge it? the water in that chamber should be flowing well being its the same chamber where the powerhead is. the power head is located directly unber the heater.
I don't know where the temp sensor is in your particular heater....read the instructions and see if it says completely underwater or to leave the top out....

Do you have a seperate thermometer? It might be a good ideal to get another one just to make sure the digital one is correct... it might be bad....

oh it was right. I have one on each side of the tank. my heater is a hydor theo 50W. I'm on my way home right now to see whats going on houres after the incident. Will update when i get home
Hey again, The heater sensor is somewhat in the middle. I got the Hydor theo 50w. I just got home and check my tank temp with the light running from around 2pm est. and the temp is ok @ 78.1 deg. Ofcourse I unpluged the heater this moring and its been ok till now. Will it work you think I'f I was to set the temp on my heater to about maybe like 72 which it would heat it up a little and not to the crazy temp of 87.9 being that since the water temp was about 77 deg when installed it yesterday and i set the heater temp to 78 deg and it most likley stayed on all night it seems since my water today was at 87.9 when i got up @ 6am today.
Does it have a light on it so you can see when it is running?

I would suggest making it visible for a bit and keep an eye on it until you feel comfortable the unit itself is working.

Better safe than sorry. Every thing you are doing should work, I would just keep a good eye on things for a couple of days.

also make sure your heater is working properly. heaters will come on and when they reach a certain temp will turn off and then back on when cooled. so maybe the heater is set too high. turn on the moon light and after a while touch it and see how warm it is. if you do not have any air movement under the hood where the night light is the moon fixture might increase water temp. you could do the moon light from outside the tank through the glass. just a thought. good luck let us know what you find out is causing your temp rise.
well last night i left the moonlight on all night long and i check the temp and it was at 78 all night long. It seems that it wa the heater causing the issue. I turned it down to about 74 deg so it wont go off untill it heats 74 degrees in that chamber. Can you guys tell me what types of coral i can add to my original 12G nano cube that brings the 24w 50/50 lights? I dont want to add anything in thre that i might end of killing :mrgreen:
I have seen some really nice nano tanks with pretty much all different types of zoanthids... lots of different colors... mushrooms or leathers would also work, but LPS, SPS would need more lighting.