Protein Skimmer Calculator
Find the right protein skimmer for your saltwater aquarium. Get the ideal skimmer rating, pump flow, and air intake based on your tank volume, bioload, and tank type.
How the protein skimmer calculator works
This calculator helps you select the right protein skimmer for your saltwater aquarium. Based on your tank volume, bioload (light to very heavy), and tank type (fish-only, reef, or mixed), it determines the recommended skimmer processing capacity in litres per hour (L/h).
Enter your tank details below, choose your bioload and tank type, and the calculator instantly shows your recommended skimmer size, pump flow rate, air intake, and a comparison across different skimmer classes.
Step 1: Tank Information
Understanding Bioload
Bioload refers to the waste produced by fish, invertebrates, and corals. Higher bioload requires a more powerful skimmer. A heavily stocked tank needs 3.5–4.5× turnover per hour, while a lightly stocked tank needs 2×.
Step 2: Skimmer Preferences
Skimmer Sizing Guidelines
For a typical reef tank, choose a skimmer rated for 2–4× your tank volume per hour. Light bioload → 2×, medium → 2.5–3×, heavy → 3.5–4×, very heavy → 4.5× or more. This calculator helps you dial in the exact number.
Skimmer Results
Recommended Skimmer Rating
Skimmer Class Comparison
| Skimmer Class | Rating (L/h) | Pump Flow (L/h) | Air Intake (L/h) | Best For |
|---|
Skimmer Capacity Breakdown
Skimmer Sizing Formula
Skimmer Rating = Tank Volume × Bioload Factor × 1.0 (adjustment)
Your skimmer should process 2–4.5× your tank volume per hour, depending on bioload. This calculator uses your selected bioload factor and tank type to recommend the optimal rating.
Frequently Asked Questions
What is a protein skimmer?
A protein skimmer is a device used in saltwater aquariums to remove organic waste, proteins, and other dissolved compounds before they break down into harmful substances like ammonia and nitrates.
How do I size a protein skimmer for my tank?
A general rule of thumb is that your skimmer should process 2–4 times your tank volume per hour. Lightly stocked tanks need 2× turnover, while heavily stocked tanks need 4× or more. This calculator uses your bioload and tank type to determine the right size.
What bioload factor should I use?
Bioload factor ranges from 2 (light) to 4.5 (very heavy). Light bioload means few fish and low feeding, while very heavy bioload means many fish, heavy feeding, or a coral-heavy reef system.
What is the difference between in-sump and hang-on-back skimmers?
In-sump skimmers sit inside the sump below the tank and are generally more powerful and efficient. Hang-on-back (HOB) skimmers attach to the back of the tank and are easier to install but typically have less capacity.
How often should I clean my protein skimmer?
Clean the collection cup every 3–7 days, and perform a full cleaning of the skimmer body and pump every 1–3 months, depending on bioload and skimmate production.
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