Fish Keeping Gear Guide

Common Filtration Questions

My filter says it's rated for my tank size — why do people recommend more?

Manufacturer "gallon ratings" are often tied to frequent filter media replacements and simplified assumptions about bioload. In real aquariums, flow naturally drops over time and fish produce more waste than those ratings account for. We recommend slightly more filtration because having a buffer helps keep water parameters stable — and stability is always better for fish health than running at the edge.

Can you have too much filtration?

You can have too much flow, but it's very hard to have too much filtration. Filtration is about biological capacity, not water movement. If fish are being pushed around, the solution is usually to soften or redirect flow — not remove filtration. Stable, well-buffered filtration supports long-term fish health.

Is high flow bad for fish like Bettas or Gouramis?

Yes. Strong, constant flow can stress slow-swimming or long-finned fish. That doesn't mean you need less filtration — it means you need gentler flow distribution. Baffles, spray bars, or sponge-based filtration allow for strong biological filtration while keeping the water calm.

Do I need to replace my filter cartridges every month?

In most freshwater tanks, no. Filter media holds beneficial bacteria that process waste, and replacing it too often can destabilize the tank. Routine maintenance usually means gently rinsing media in tank water and replacing it only when it physically breaks down. That's why custom, trim-to-size filter media often works better for long-term stability.

Will adding a second filter help my tank cycle faster?

Not directly. Cycling depends on bacterial growth, which takes time regardless of how many filters you add. A second filter can increase biological capacity and future stability, but it won't skip the cycling process. Patience and proper setup matter more than adding equipment.

Should I upgrade my filter media?

Stock cartridges work, but custom media often performs better long-term. Cut-to-fit sponges support larger bacterial colonies, Purigen polishes water crystal-clear, and bio-rings like Matrix or BioMax add biological capacity. Upgrade when you want more stability or clearer water between maintenance.

Do I really need water conditioner for every water change?

Yes. Tap water contains chlorine or chloramine that kills beneficial bacteria and harms fish. Even "small" water changes need conditioning. Prime is highly concentrated—just 5ml treats 50 gallons—making it cost-effective and safe for daily use.