Will this work?

[oyam123]

Now that the eel has a new home and i gave all my FW fish away, I have a 120 gal. in the living room with 100lbs of LR in it (oh and a hermit crab).
I plan to keep it SW, but dont like runing a skimmer and pumps on it cuz of the vibration it gives off. I plan to run two RENA XP3 filters on it, do you think it will cut it.

[Ben]

Those are like 300 gph cannister filters, right? If so, that won't be enough flow by a sizable margin unless you are going for stagnant lagoon with plenty of macroalgae or plants, but it will be fine for filtration if you keep the tank very lightly stocked and remember to clean the cannisters as the directions indicate.

Stock it more like a 30-60 gallon tank and you'll probably be OK if you add another 500-1000 gph of flow. Lagoonal species will tolerate the conditions far better. I wouldn't try open reef fish or corals in that.

[oyam123]

FLOW? so if i add a SEIO 2600 will that help?
or is it the flow going in and out of the filters?
2x300=600 gal/hr of filtration.

[Ben]

I meant total flow of water through the tank. 10x the tank volume in GPH is sort of a rule of thumb minimum with more like 20x - 40x being appropriate for some species. The lower the flow, the more stagnant the water, and in the ocean semi-stagnant water = tide pools and lagoons.

There's another option, make it a tide pool tank.

[oyam123]

I hope to get some more rock soon, and re-do the 120.
2-RENA XP-3 filters, I plan on PH to do a wave action (maxi or SEIO).
I will also go with MH on this one.....If someone has more info on lagoon type setups please LMK.