ATO 3155 vs Osmolator 3

Tinklez

Active Member
View Badges
Joined
Oct 10, 2025
Messages
222
Reaction score
90
Location
Texas
Rating - 0%
0   0   0
Hi everyone. What’s you’re thoughts on the old model of 3155 vs the new osmolator 3 for a ATO for a 50 gallon AIO?

From what I’ve read, 3155 is the best, has worked for years for many people, thought it is loud.

For the new Osmolator 3, I’ve read mixed reviews. It doesn’t have the physical floating nob, some have said it has malfunctioned, although it is a lot quieter.

Which one do you think I should purchase?
 

Gumbies R Us

God, Bouldering, and Reefing
View Badges
Joined
Nov 10, 2022
Messages
28,984
Reaction score
51,370
Location
North Georgia
Rating - 0%
0   0   0
I have the older one (nano version) and have never once had issues with it!
 

cdemoss01

5000 Club Member
View Badges
Joined
Sep 8, 2023
Messages
6,052
Reaction score
21,172
Location
Roanoke
Rating - 0%
0   0   0
The 3155 is probably your better choice. But I wanna bump this so others can put in input.
Why do you think the older one is better? Have you heard alot of negative reviews about the new one?
No.. id just think the newest one would be a bit better, what's your main concern?
 

Undersea Gardens

Community Member
View Badges
Joined
Dec 4, 2022
Messages
69
Reaction score
57
Location
Canada
Rating - 0%
0   0   0
For me the 3155 is the better choice but only because of application. My RODI reservoir is at least 50 feet away from my sump. It was very easy to lengthen the pump wiring to accommodate with some speaker wire. I can't do that with the new Osmo 3.
 

TOP 10 Trending Threads

WHAT AMOUNT OF LIVE ROCK AND SAND SHOULD BE PRIORITIZED FOR OPTIMAL BIODIVERSITY/FILTRATION?

  • 100% live rock + bagged sand

    Votes: 37 27.4%
  • 100% dry rock + 100% live sand

    Votes: 46 34.1%
  • 50/50 live/dry rock, 50/50 live/bagged sand

    Votes: 30 22.2%
  • 75% live rock, 25% live sand

    Votes: 12 8.9%
  • 25% live rock, 75% live sand

    Votes: 10 7.4%
Back
Top