Octupus HOB - Change pump to Maxi-Jet???

Husky_1

Premium Member
I know from reading the main Octupus Mod thread that a lot of people have modded their normal Octopus skimmer by putting different pumps in. I, however, did not notice if anyone has done this with Reef Octopus HOB-100 skimmer.

I really want to try attempt this on my HOB skimmer to save heat and footprint, but have a few question.
Has anyone changed out the Resun King pump for a maxijet (or other small pump) on the HOB skimmer?
If so, did you have to do a needle wheelmod, or was the normal venturi on it ok?
If it has been done, what size pump did you use, and what did you do to attach the pump to the inlet?


Here is the background on why I want to do this:

When I first setup my tank, 38gallon without a sump or chiller, my temp ran around 72 degrees. I had a Maxi-1200, a whisper 40, and a corallife 100watt light fixture for heat sources in the tank. Then a few weeks later I added a Seio 620 and the Octopus HOB-100 on the same day. At this point my tank went up to 80 degrees. This temperature was acceptable, but arguably on the high side. Well yesterday I added a glass hood to the tank, and now the temp is at 83 degrees. Now when I get some real lighting, the temp will probably shoot up a bunch more, and even if 83 is ok, 2-5 degrees more will not be acceptable. I do not want to take the glass top off the tank because of a few reason, namely fish jumping, save on evaporation, and my cat. So the only option I have is to figure out what the temp load the Seio and the skimmers' Resun King pump adds to the system. I have unplugged the Seio, and will look to see what the temp difference is tomorrow. The following day I will unplug the skimmer, and then wait a day to see the difference again. I really feel that the skimmers pump, the Resun King, is the reason for the heat, given its size and loudness compared to the other pumps. I may end up replacing the SEIO with a modded maxi-jet 400 regardless, because of its size in the tank. I wont be wasting any money because I will just use that pump for the QT tank.

Thanks for the help
 

RichConley

New member
The resun Kings are actually decent pumps. Very similar to Sedras.

for submersible pumps, wattage = heat. A 20w maxijet is teh same as a 20 watt tunze is the same as a 20 watt heater. Just look at the wattage draw.


Is the resun king a needlwheel, or is it being used to push a venturi?
 

Husky_1

Premium Member
The resun is a needlewheel, from what I remember, but I do not know for sure. It does have the airline, but I think this is common between venturi and needlewheel.

As far as the wattage goes, I can get the MJ 900 which is only 8.5 watts, and pushes 230gph where the resun pushes 225. So there would be some nice power savings.

I also have a seio 620, and will probably change this out for a modded MJ-900
 

mcintosh

New member
I am interested in how your tests came out. Did the skimmer pump boost the temp more than the Seio?

Just wondering.
 

RichConley

New member
I'm pretty sure its a Resun225, which pulls 19w(probably about 10 when pulling air). It also will do 6' of head, whereas a mj900 will only do about 3.5. How much air is it pulling? I'm pretty sure its a LOT more than a MJ900
 

Husky_1

Premium Member
I did a test with turning each one of individually only affected the temp by about 1 degree each. The seio was turned off for about 20 hours, whereas the Resun King was off for about 2 days. To be a little more accurate I will probably turn off the seio for the same amount of time.

No matter what happens with shutting the seio off for a little more time, it is hard for me to understand, because when I put both of them in the system the system raised 6-8 degrees. I am pretty sure the lighting times have stayed the same, and the MJ was always in the system. I guess my next step is to turn both off, and see what happens. I cannot imagine that both of them together would put of more heat then either of them seperately though.

As far as how much air it pulls in, I do not have the equipment to measure it, but if the effective temp on the system is only 1 degree then I will probably just keep the Resun King for the skimmer.
 

RichConley

New member
Husky, the glass top is the majority of your problem. Before, added heat wasnt so bad, because it could escape. When you added the glass top, you took away evaporative cooling.
 

Husky_1

Premium Member
Rich, Obviously you are correct about the glass cover, but as I stated, this is the last thing that I want to change at this point. Thats not to say that I will not, its just the last option I want to explore.
 

mkarston

New member
I think if you can exhust the heat away from tank to start with, it glass top will become less of an issue. That is if the tank isn't hot to begin with, there is no heat that needs to exscape, and the glass top can stay.
 
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