AqAdvisor Alternative: A Modern Aquarium Stocking Calculator
If you've planned a fish tank in the last fifteen years, you've probably used AqAdvisor. It has been the community's go-to stocking tool for over a decade, it pioneered the whole category, and plenty of experienced keepers still swear by it. So why would you want an alternative? Mostly for the same reasons people search for one: a dated interface, results that can be hard to interpret, and a desktop-era design that fights you on a phone. This page compares the two tools honestly, including where AqAdvisor is still the better pick, and lets you try our calculator right here on the page.
Two different philosophies
AqAdvisor's strength is its depth. Its stocking formulas have been refined over many years of community feedback, and its species database runs into the hundreds. That history is real and it deserves credit.
The trade-off, and a common complaint among keepers, is transparency and usability. AqAdvisor tells you a stocking percentage and a filtration figure, but it can be hard to see why it flagged something, or which fish on your list is the problem. The interface also predates modern mobile browsing, so many keepers find it awkward to use on the device they actually plan tanks on.
The FishAuthority calculator takes the opposite approach: fewer species, fully explained results. Every warning names the exact species involved and the exact rule it broke:
- Minimum tank size: "This fish needs at least X gallons as an adult."
- Schooling group size: "This species should be kept in a group of N or more."
- Temperament: known fin-nippers, predators, and territorial conflicts, called out by name.
- Water parameters: temperature and pH ranges that don't overlap between your chosen species.
It's built mobile-first, loads fast, and covers both freshwater and saltwater tanks, including reef-safe and aggression checks on the marine side.
Try it right now
The best way to compare stocking calculators is to run the same stock list through both. Here's ours, live on this page, no signup and no separate tab needed. Pick a tank size, add your fish, and watch the warnings explain themselves. If you keep a reef, switch over to the saltwater version, which adds reef-safe and aggression checks on top of the bioload math.
When AqAdvisor is still the better choice
An honest comparison has to go both ways, and there are real cases where AqAdvisor remains the stronger tool:
- Uncommon species. AqAdvisor's database covers hundreds of species. Ours is a curated set of roughly 37 popular freshwater fish plus a marine lineup, chosen because they cover the great majority of community tanks. If you keep oddballs, rare cichlids, or obscure catfish, AqAdvisor is more likely to have them.
- Filtration modeling. AqAdvisor lets you specify your exact filter model and factors its rated turnover into the result. Our calculator uses a simpler filtration input, which is enough for most setups but less granular.
- Track record. AqAdvisor's numbers have been sanity-checked by an enormous community over many years. That accumulated feedback is worth something, especially for unusual combinations.
Many keepers get the best of both: use AqAdvisor for a second opinion on an unusual species, and use ours when you want to understand exactly what a warning means and fix it.
Side-by-side comparison
| Feature | AqAdvisor | FishAuthority |
|---|---|---|
| Species database size | Hundreds of species | Curated ~37 freshwater + marine set |
| Mobile experience | Desktop-era layout | Mobile-first, responsive |
| Explained warnings | Percentage-focused; reasons can be opaque | Every warning names the species and the rule |
| Saltwater / reef mode | Limited | Dedicated marine calculator with reef-safe and aggression checks |
| Filtration detail | Specific filter models | Simplified turnover input |
| Free, no ads | Free, ad-supported | Free, no ads, no signup |
| Actively maintained | Long-running, infrequent visible updates | Actively developed |
What people searching for an AqAdvisor alternative usually want
When keepers go looking for sites like AqAdvisor, it's rarely because the math failed them. In our experience the wish list looks like this:
- A phone-friendly tool. Most tank planning now happens in a fish store aisle or on the couch, not at a desktop. A calculator that pinches and zooms poorly gets abandoned.
- Answers, not just numbers. "You are at 112%" is less useful than "your bristlenose pleco needs a 29 gallon minimum and your neon tetra group is below its schooling size." Knowing which fish caused the flag tells you what to change.
- Saltwater support. Marine stocking has its own rules (reef-safe status, one-per-tank species, tang space needs) that freshwater-focused tools don't model well.
- A clean, current experience. No clutter, no ads, and a tool that visibly keeps improving.
If that list matches yours, our calculator was built for you. If your priority is the deepest possible species database, AqAdvisor still earns its bookmark, and there's no rule against using both.
What no calculator can do
Here's the part both tools agree on: a stocking calculator is a planning aid, not a verdict. Individual fish vary in temperament, tank footprint matters as much as volume for active swimmers, and a well-cycled, well-maintained tank can carry a load that would crash a neglected one. Whichever tool you use, cycle the tank first, stock gradually, keep up with water changes, and read a proper care sheet for every species on your list. If two calculators disagree, that's not a bug in either one; it's a reminder that the numbers are estimates and the margin belongs to your fish.
Frequently Asked Questions
Is there a modern alternative to AqAdvisor?
Yes. The FishAuthority stocking calculator is a modern, mobile-friendly alternative that explains every warning it raises (minimum tank size, schooling group size, temperament, and temperature/pH overlap), covers both freshwater and saltwater, and is free with no ads. AqAdvisor remains a solid tool with a much larger species database, so many keepers use both.
Is AqAdvisor still accurate?
AqAdvisor's formulas have been refined by community feedback for well over a decade and are broadly reasonable as a starting point. No stocking calculator, ours included, replaces researching each species. Treat any calculator result as guidance and confirm details against reputable care sheets.
Why does my stocking percentage differ between calculators?
Different calculators use different bioload models and capacity assumptions, how much waste each species is assumed to produce and how much a given tank and filter can process. A 15 to 20 point difference between tools is normal. Treat both numbers as guidance, keep a comfortable margin, and let species-specific research make the final call.