High Tide Aquatics

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Bruce Spiegelman

Bruce Spiegelman

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Here's a pic of the living room and the wall where the new tank is going. It has a couple of standard two outlet plugs. What do I need to do to make sure there's enough power here and it's safe? Tank is 6 X 36 X 20. 250ish gallons.

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How permanent can your changes be?

A simple solution, depending upon how easy it is to access, is to run 12-3 wire. This allows two 20 amp circuits sharing a common neutral. Fat junction box with multiple plugs then you can plug everything.into that, dj power strip, apex whatever
 
A hot conductor, PG&E typically brings in 240 to a house, 2 hots and a neutral, but the hots are out of phase with each other so you can share a neutral with no worries of overloading the neutral. Presumably you'll have an electrician doing this work for you? In which case just point where you want outlets and tell him how many. circuits, 2 -20amp is what I would hit at a minimum. Depending upon how electrical intensive you plan on getting, i.e. how many heaters, chillers, 3x400w metal halides? :D
 
A circuit is 120 volts a hot which is the black wire typically , a white wire which is the nuetral and a green wire which-is the ground.
 
Two 20A circuits is more than enough. Do yourself a favor though and put in GFCIs. Don’t put them behind the tank though, put them elsewhere in the room where the reset buttons will be easy to get to and then daisy them to a pair of weather resistant outlets behind the tank.
 
Two extra notes. I may not have halides, but a pair of 20 A circuits is happily feeding my 600 gallon system in TX.
You should consider oversizing the wiring. For our usage the payoff time for thicker copper due to lower resistance loss in the line is often short enough to consider. Some quick math will answer that question.
 
@Bruce Spiegelman, with the kinds of questions you’re asking I think the professional electrician is probably your best option. At least finding an electrician who is willing to walk you through step by step what you need to do.
 
Bruce Spiegelman said:
I'm considering doing it myself to save money. What's a circuit?
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Don't.
If you don't know what a circuit is, you should not be learning using 120/240V.

My setup:
2 x 120V circuits. 20A each. Out of phase.
I have a 240V (dual leg) wired in surge protector at my outlets.
I then split each one into 4 sets of 2 plugs. So 16 total plugs.
Each pair of plug is an independent GFCI, in parallel, so one does not trip the others.
 
jccaclimber said:
Two extra notes. I may not have halides, but a pair of 20 A circuits is happily feeding my 600 gallon system in TX.
You should consider oversizing the wiring. For our usage the payoff time for thicker copper due to lower resistance loss in the line is often short enough to consider. Some quick math will answer that question.
Click to expand...
Depends how far you tank is from the main panel. Larger conductors are mainly for voltage drops over large distance.
Usually equipment operates 90-120 VAC. Usually a 20 amp circuit should have a load about max 15amps
 
dswong01 said:
Depends how far you tank is from the main panel. Larger conductors are mainly for voltage drops over large distance.
Usually equipment operates 90-120 VAC. Usually a 20 amp circuit should have a load about max 15amps
Click to expand...

NEC says 16 max, so that sounds perfectly reasonable. Loss is also a function of current, not just distance, and why one should do the math on conductor loss. IMHO anyone who can't either do the math on conductor loss or know how to size conductors per the NEC isn't in a great spot to be running new circuits from the panel. It's just V=IR, V is predictable, I can be measured or added up, and there are published tables for R. Most of my devices (lights, return pumps, powerheads) are all DC devices so while their power supplies are capable of operating with a very wide input voltage the power supplies are also going to draw more current if the voltage is lower so that they can output the correct amount of power. My LEDs don't dim if the wall voltage drops, even if the few remaining incandescent bulbs in the house do.

To put some numbers to it
Take my case at the last place, 100' run to the box (across the garage, up to the attic, across the house, back down to the 1st floor), so 200' round trip for the portion I have easy control over. Say I'm running a 15 A circuit and opt to use 14 gauge copper. Also assume I'm running 10 A at 120 V. R = 0.505 Ω/200', so power lost to the line is roughly 50.5 W. Arguably a bit higher as the device will want to pull more power.

Say you step up to 12 gauge, which you'd need to do in order to run a 20 A circuit anyways. Now you're only losing just shy of 32 W. Bump to 10 gauge just because you can and it's roughly 20 W. Assume 12 hours/day and $0.25/kW-hr and you have $33.44 per year in electrical savings going 14 ga to 10 ga. Plan to keep the tank 10 years and it's $334.42 in electrical savings. Subtract whatever the difference in wire cost is. Right now going from 14/2 to 12/2 is <$20 difference for a 250 ft spool. Going 10/2 is a much bigger jump in price so maybe not worth it. Wire cost mostly scales with the shorter run, although the loss decreases too. We could debate future value of money too vs investing in wire, but I'll leave that to someone more versed in it.
 
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