Coralife Biocube 29 Heat Issues

[rain]

Ok everyone. I know this is a common problem with the Biocubes, but I need some help.... I have a Coralife Biocube 29. I have the Steve's LED lighting in it, a Jebao WP-10 wavemaker, and a Koralia Nano 425. The flow has been good and all water parameters are great with the exception of alkalinity running a tad low (7-8 even when calcium is good at around 420, thinking about trying a little baked baking soda... another topic but welcome ideas on this too).

 

With the stock biocube return pump I was running around 79.8 at night and around 81-81.5 during the day. This is with the house at around 74-75 degrees. Not terrible but everyone seems to think a little cooler is better. So, with loads of research, I decided to upgrade my return to the Cobalt MJ1200. A lot of people really love them for the biocube. I installed it last night and bam, my temp overnight shot up to 81 and during the day was around 82.4. So my attempt to lower the temp a little did the opposite. Advice? Should I just return the MJ1200 and go back to the stock pump and call it a day? Should I try the MJ900 (people say that it is a lot lower watts so it puts out less heat). Thanks for any ideas!

[Origami]

Go back to the stock pump or to the MJ900. Consider that virtually all power that goes into the pump is converted to heat. (It's really not, but it's a good starting assumption.) So the wattage saved results in less heating of the water. 

 

As for the alkalinity, regular baking soda will do just fine. You don't need to bake it unless you have a tank who's pH runs unreasonably low. In this case, the baked baking soda will tend to absorb dissolved CO2 in your water and temporarily raise your pH (and rather quickly, I might add). 

 

I like to use Jose Dieck's reef chemistry calculator when determining how much additive to use. It's been a handy companion for many years now.

[rain]

Thanks Tom! Very helpful and I appreciate the advice!

[Happyfeet]

I'm suprised your Cobalt MJ1200 raises the temp that much. Mine actually lowered the temp, I figured there was less friction in the MJ1200 as opposed to the MJ1200.

 

Origami is right on the money though, conservation of energy.

 

Whats wrong with 7-8 in Alkalinity? I keep mine at 8, I find I have better colors, better growth, and less unexplained coral deaths when the alkalinity isn't really high.

[rain]

I was surprised too. I'm going to send it back and try the MJ900. Way lower on watts than the stock pump or MJ1200.

 

You know, I did raise the alkalinity to 11 and now my corals look POed. I think you are right and I'll be content with my stable 7-8 level. I know people advise not to stress on hitting a specific number but as a newbie it takes time to relax. :-)

 

Thanks!!

[khh27]

I was surprised too. I'm going to send it back and try the MJ900. Way lower on watts than the stock pump or MJ1200.

 

You know, I did raise the alkalinity to 11 and now my corals look POed. I think you are right and I'll be content with my stable 7-8 level. I know people advise not to stress on hitting a specific number but as a newbie it takes time to relax. :-)

 

Thanks!!

May have raised your alk too fast also

[rain]

Yup I think I did.... Live and learn.... It's going back down slowly so I think it will recover.

[rain]

Happy to report that my tank is happy and stable with the MJ900. Hovering around 79.5-9 at night and 81 during the day. Corals are happy. It's not really any better than the stock Coralife pump but now at least I have a spare handy just in case.

[Djplus1]

If the flow through the back is an issue, I would use the MJ1200 and ditch the Koralia. You probably can get by on one power head. If you search this forum I did a fan install on my 14g Biocube. Though I did end up changing the fan placement to the left side rear of the lid instead of the access door.

[rain]

The flow in the back seems ok for now but I'll keep that in mind. Thanks!