How to Start a Saltwater Aquarium: The 90/10 Method
Starting a saltwater aquarium doesn’t have to be complicated. The 90/10 Method simplifies reefing by focusing on the 10% of actions that produce 90% of long-term success. Rather than chasing every gadget or theory, this approach gives you a clear, proven path from day one. Begin by choosing a tank in the “Goldilocks zone” — around 40–75 gallons for the best balance of stability and simplicity. Use dry rock and sand to create a functional aquascape, install a reliable heater, return pump, and light, and start the nitrogen cycle with pure RODI water and quality salt mix. Once stable, add a small cleanup crew, then hardy fish and corals slowly. The 90/10 Method teaches you exactly when and how to take each step, removing the guesswork that causes most new reefers to fail. With this method, you’ll spend less time fighting problems and more time enjoying a thriving, beautiful saltwater reef.
Six Core Principles Every New Reefer Should Know - 90/10 Method
We want you to enjoy reefing and to get that first big win. Too many new hobbyists spin their wheels, spend money, and lose fish and corals because they try to invent everything from scratch or follow advice that only worked for lucky or highly experienced reefers. These six core principles are the things we wish someone had told us on day one. Understand them and you dramatically increase your chances of success.
90/10 Part 1: Tank Type, Size, Source Water, Substrate, and Rock
Serious Reefs developed the 90/10 Method to give nearly everyone a straightforward path to a beautiful reef tank with minimal effort. The idea is simple: choose the highest-success option at every decision point so that 90 percent of people reach the finish line, and do it using roughly 10 percent of the effort and complexity typical of hobbyist approaches.
90/10 Part 2: Filtration, Phosphate, Flow, Heaters, & Lighting.
Dilution over filtration. Perform ten percent weekly water changes to stabilize pollution and buffer additive imperfections. Add skimmers, filters, or refugiums only to solve specific problems, not by default.
90/10 Part 3: Chemistry, Evaporation, Testing, & Utilitarians
The 90/10 method is simple: help nearly everyone succeed (the 90%) while using the least amount of effort possible (the 10%). For chemistry and maintenance we recommend practical, low-cost solutions that are easy to learn and automate once you understand how your tank behaves. The result is a stable, healthy reef without spending unnecessarily on complicated systems.
90/10 Part 4: Biome Cycle Explained
Starting a reef tank doesn't have to feel like playing roulette with algae, slimes, and unexplained coral losses. The 90/10 Biome Cycle gives us a low-effort, high-reward approach: do the right small things in the right order and we capture about 90 percent of the success with roughly 10 percent of the fuss.
90/10 Part 5: A Modern Reef Tank Build List
It’s time to take everything we’ve learned in the 90/10 series and apply it to a real tank build, beginning with the system design and selecting the right gear for the tank.
The design phase is never cheap, but along the way we’re going to challenge the idea that reefing has become more expensive by comparing the cost of this build to Ryan’s first tank from 2004, more than twenty years ago. Spoiler alert: modern approaches to reefing can actually make it cheaper, even without factoring in inflation.
“But Can I Change This?”A Hybrid Reef Tank Build- 90/10 Part 6
This build shows how to use the 90/10 recipe as a baseline and make smart adjustments that fit your time, budget, and environment. For this hybrid tank we are following the 90/10 principles, but bending a few of them to meet the unique needs of the studio.