Nobody buys a filter because they're excited about filters. They buy one because the alternative is cloudy water, a stressed tank, and a very unimpressed fish staring back at them.
Simply Fish carries aquarium supplies in NZ that do the unglamorous, essential work behind every healthy tank: filtration, heating, circulation, lighting, the lot. This is the gear that does more for your fish than anything else in the tank.
Picking the right aquarium filter in NZ means knowing the types on offer, not just guessing by tank size. Internal filters sit inside the tank and suit smaller setups where space is tight, while hang-on-back units clip to the rear and free up room inside for plants or decor. Canister filters handle bigger volumes and heavier bioloads, and sponge filters offer the gentlest flow, ideal for fry tanks or delicate species.
Rather than picking by tank size alone, match the flow rate to your actual litres and stocking level, since a heavily planted or crowded tank needs more turnover than a bare one. Our internal aquarium filters and hang-on-back filters range covers most starter setups.
Heater wattage isn't a flat number that scales neatly with tank size. Room temperature, tank shape, and how exposed the glass is all shift what you'll actually need, so treat any wattage chart as a rough starting point rather than a rule. The listed spec on each aquarium heater NZ product page is the more reliable guide, especially for anything outside a standard rectangular tank.
Whatever heater you land on, pair it with a reliable way to check the result. Our aquarium thermometer range makes it easy to confirm the water's actually sitting where you set it, rather than trusting the dial alone.
Flat, still water isn't doing your fish any favours, even in a filtered tank. Good circulation keeps oxygen moving through the water column and stops waste from settling in corners that no filter can reach. Air pumps add extra surface agitation and gas exchange, and are particularly useful in heavily stocked tanks or anywhere filtration alone isn't quite cutting it.
Our air pumps and aeration range covers everything from whisper-quiet single-outlet units to larger units built for larger systems.
Before anything goes in the tank, plan where each piece of gear will actually sit, since retrofitting around fish and plants is far more stressful than doing it up front. Lighting matters too, not just for plant growth but for how the whole tank reads day to day. Our aquarium lighting systems range covers options for planted tanks through to simple viewing lights.
Leave new equipment running for a few days before adding fish, so you can catch any issues while the tank's still empty.
Your equipment needs upkeep as much as the fish do. Rinse filter media in old tank water rather than tap water to protect the bacteria doing the actual cleaning work, and check impellers and intakes regularly for debris that can quietly wreck flow rate over time.
Heaters and thermometers are also worth a periodic check. A heater left on or a thermometer reading incorrectly can go unnoticed for weeks before anyone spots the problem.
Guessing at equipment is how good tanks turn into expensive mistakes. Ask our team before you buy, or browse the range and check individual product specs as you go. Either way, we're happy to help you get it right the first time.
Contact usCheck the flow rate listed on the product page against your tank's litres, then adjust up if it's heavily stocked or planted.
Most filters run mechanical, biological and chemical media together. Only the biological stage needs to stay untouched during cleaning.
Near the filter outlet, so the current spreads warmth evenly rather than leaving cold spots elsewhere in the tank.
Little and often. Rinse media in tank water every few weeks rather than doing one big clean that disturbs everything at once.
Usually, though it's worth checking compatibility notes on the product page, especially for filters and lighting fittings.
