Electrical requirements for a 120

[theclownshow]

I’m building a 120 gallon reef tank with the following equipment

2 Nicrew 150’s
2 power heads
Return pump
Skimmer
2 300 watt heaters with ranco controller
ATO
1-2 dosing pumps

Robo tank controller

My current circuit by the tank is 15 amp.

I have good access to under the tank from the basement and can run wire from the panel right to it.

I am going to use a 20 amp GFCI breaker at the panel. My question, is one enough? Should I add a second to split up the equipment? Thanks

 

[TylerHaworth]

A bit unclear, are you saying you’ll have a 15 and a 20 or just a 20?

In any case a single 20 should be fine, but if I had the option I’d split the load.

 

[exnisstech]

I'm not an electrician but I've always been told not to swap 15 amp breakers with 20amp because the wiring in the house may only be rated for 15 amps. FWIW all my tanks run on 15 amp circuits with no issues even on my 330 that has 14 power bricks along with other stuff.
EDIT sorry I misread and now see you are running a circuit not swapping breakers. Probably be best to calculate the load from all the equipment you'll be running to get an idea what the max draw will be.

 

[jsmkmavity]

a single 20 amp circuit might be enough for the tank, but it is marginal and 2 circuits are a great way to build in redundancy. If each circuit has at least 1 heater, pump, light,etc. The tank will still be runing if 1 breaker trips for some reason. Think about what lighting upgrades you might want in the future. A 20 amp circuit is only rated for about 1920 watts of continuous load (lights and pumps + anything running 3+hours at a time).
A 15 amp circuit is only rated for 1440 watts under the same conditions. Although heaters arent usually technically a continuous load it is almost impossible to know how many are going to be running for how long so i usually consider everything in a reef tank continuous load for easy calculations and extra safety margin.

 

[theclownshow]

A bit unclear, are you saying you’ll have a 15 and a 20 or just a 20?

In any case a single 20 should be fine, but if I had the option I’d split the load.

I have a regular 15 amp circuit. For my living room outlets. I’m thinking if I do 2 circuits I run wire for a 20 amp GFCI circuit and I replace the 15 amp breaker with a 15 amp GFCI. That would give me a 20 and 15 amp GFCI to work with

 

[TylerHaworth]

I think you’ve got a solid plan, should be more than sufficient.