By the Innovote Trade Desk. Innovote Global is an Egyptian importer and sourcing partner serving distributors, retailers, manufacturers, and overseas suppliers. Documentation supporting compliance with the relevant authorities’ requirements is available on request. This article is general information, not legal advice.
Related reading:
– Importing into Egypt: the complete guide
– NFSA food import licensing in Egypt
– Incoterms explained for Egypt importers
By the Innovote Trade Desk. Innovote Global is an Egyptian importer and sourcing partner serving distributors, retailers, manufacturers, and overseas suppliers. We do not sell to consumers or provide setup or maintenance services. Documentation supporting compliance with the relevant authorities’ requirements is available on request. This article is general information, not legal advice.
Related reading:
– Importing into Egypt: the complete guide
– Importer of record: who carries the liability at Egypt’s border
– Our partners and distribution network
A heater that is too small never reaches set temperature on a cold night; a heater that is too large overshoots and cooks a tank when the thermostat sticks. The working answer for most freshwater tropical tanks is roughly 1 watt per litre when the room sits close to target temperature, rising toward 2.5–5 W/litre as the gap between room and tank widens. Chillers are a separate calculation entirely, sized in BTU/hr from water volume and the temperature drop you need. This guide gives a shop the tables, the safety logic, and the stocking shortlist to advise customers correctly — and to avoid the warranty returns that come from guessing.
Temperature is the single most common reason a healthy-looking tank crashes. Fish are ectotherms; their metabolism, immune response, and oxygen demand all track water temperature. A swing of a few degrees in a day stresses stock, and a stuck heater or an untreated summer heatwave kills it outright. Getting the heating and cooling specification right is the difference between a customer who returns for livestock and one who blames the shop.
Every heater is a resistive element plus a thermostat. The element converts watts to heat; the thermostat decides when to stop. Sizing is the act of matching the element’s output to the rate at which the tank loses heat to the room. If output exceeds loss by a wide margin, the element spends most of its life switched off and cycles aggressively — hard on the thermostat contacts. If output cannot keep pace with loss, the heater runs continuously and still never reaches set temperature.
Two variables drive the calculation: water volume and the temperature delta between the target tank temperature and the coldest the surrounding room reaches. A 100-litre tank in a heated living room holding 25°C against a 22°C room is a gentle ask. The same tank in an unheated garage that drops to 12°C on a winter night is a completely different load. The volume is identical; the heat loss is not.
This is why a single “watts per litre” number printed on a box is only a starting point. It assumes an average room. Below, we separate the two variables so a shop can give an answer that fits the customer’s actual room, not an average one.
The cleanest rule of thumb in fishkeeping is about 0.5 watts per litre for every 1°C the heater must lift the water above the room’s low point. That single sentence captures both variables. A 200-litre tank that needs to hold 4°C above room temperature needs roughly 200 × 4 × 0.5 = 400 W; the same tank needing 8°C of lift needs about 800 W, which is the point at which you split the load across two heaters (covered below).
Most shops do not want to do arithmetic at the counter, so the table below pre-solves the common cases. It bands the ambient delta — the difference between target tank temperature and the coldest the room reaches — and gives a watts-per-litre figure, then a worked column for typical tank sizes. Figures are rounded up to the nearest standard heater size, because under-sizing is the failure that matters.
| Ambient delta (target − coldest room) | W per litre | 54 L (nano) | 100 L | 200 L | 350 L | 500 L |
|---|---|---|---|---|---|---|
| 0–5°C (heated room, mild) | ~1.5 W/L | 100 W | 150 W | 300 W | 2 × 300 W | 2 × 400 W |
| 6–10°C (typical home, cool nights) | ~2.5 W/L | 150 W | 300 W | 500 W | 2 × 400 W | 2 × 500 W |
| 11–15°C (unheated room, winter) | ~4 W/L | 200 W | 2 × 200 W | 2 × 400 W | 3 × 300 W | 3 × 500 W |
| >15°C (cold garage/store, extreme) | ~5 W/L | 300 W | 2 × 300 W | 2 × 500 W | 3 × 400 W | 4 × 500 W |
The bands align with the standard hobby guidance: small deltas need around 1.5 W/litre, moderate deltas around 2.5 W/litre, high deltas around 4 W/litre, and extreme cases above 5 W/litre (AquaKit heater calculator; Reef Tank Resource). The familiar “1 watt per litre” rule of thumb sits at the bottom of this range and is only safe when the room already sits within a couple of degrees of target (Aquarium Keeping UK).
Ask three questions: tank litres, target temperature, and the coldest the room gets at night or in winter. Subtract to get the delta, pick the row, and read across. A customer with a 200-litre community tank at 25°C in a flat that drops to 17°C on winter nights lands in the 6–10°C band and needs about 500 W. Round to the nearest stocked size and you have a defensible recommendation rather than a guess.
Two adjustments worth mentioning at the counter. A tank against an external wall or under a window loses heat faster than one in the middle of a room, so nudge up a band if placement is poor. And a tightly fitted lid or cover glass reduces evaporative heat loss noticeably — an open-top aquascape runs colder than a covered tank of the same volume.
Below roughly 200–300 litres a single correctly sized heater is normal and economical. Above that, splitting the total wattage across two heaters is standard practice for two reasons that both protect the customer’s stock.
First, even heat distribution. A single large heater creates a warm zone near the element and a cooler far end in a long tank. Two smaller heaters placed at opposite ends — typically one near each side of the tank, often by the filter inlet and outlet for good flow — spread the heat evenly. (Fish Laboratory)
Second, and more important, failure redundancy. Heaters fail in two ways. They fail off (element dies, tank slowly cools) or they fail on (thermostat sticks closed, tank overheats). With two heaters each rated at half the total load, a fail-off leaves the other heater able to hold most of the temperature until the customer notices. A fail-on is less catastrophic because a half-sized heater cannot drive the temperature as high as a single full-sized unit running away. Tanks over about 300 litres are generally recommended to run two heaters for exactly this reason (Pleco Feeder heater chart).
The practical rule for a shop: at 300 litres and above, sell two heaters that sum to the table wattage. For a 350-litre tank needing roughly 800 W, that is two 400 W units, not one 800 W unit.
The two common element housings are glass and titanium, and the difference matters for both safety advice and what a shop stocks.
Glass heaters carry an integrated thermostat, are inexpensive, and are the default for community tanks. The trade-off is fragility: glass can crack from a knock, from being left running out of water, or from thermal shock during a water change. A cracked glass heater is an electrical hazard in a conductive saltwater tank.
Titanium heaters are nearly unbreakable and have a small form factor, which is why they dominate larger and reef systems. Most titanium heaters ship without an internal thermostat and are designed to be driven by a separate external controller (FishLab heater controllers; BeanAnimal). That is a feature, not a gap — it moves the temperature decision out of the heater and into a more reliable, calibratable device.
Inline/external heaters sit in the return plumbing of a canister or sump rather than inside the tank. They keep the element out of the display and out of reach of large fish, and they are sized to system volume the same way as submersibles.
The most expensive failure in fishkeeping is a heater whose thermostat sticks in the ON position and slowly poaches the tank. Every internal thermostat is a single point of failure. The fix is an external temperature controller: a device with its own probe in the water that cuts power to the heater the instant the water reaches the set temperature, regardless of what the heater’s own thermostat is doing (Bulk Reef Supply heater best practices).
A controller does three useful things:
Better controllers use dual relays so a single stuck relay cannot keep the heater energised — a worthwhile upsell for reef and high-value freshwater setups (Aquatop DDC controller). Features to look for and to explain: dry-run protection (cuts power if the heater is out of water), overheat cut-off, and a temperature memory that restores settings after a power cut (AquaMiracle external thermostat heater).
Even with an integrated-thermostat glass heater, two cheap habits prevent most disasters: an independent stick-on or digital thermometer the customer actually checks, and always switching the heater off before a water change so it never runs exposed to air.
In Egypt the heating question often inverts in summer. A tank does not need a heater on a 40°C afternoon; it needs to be kept down. Heat enters a tank from three places: the room air, the lighting, and the pumps. High-output lighting is a real contributor — intense fixtures can lift a tank’s temperature by a couple of degrees per hour, while LED arrays add markedly less heat than legacy metal-halide (Bulk Reef Supply chiller guide).
The customers who most need active cooling:
Before recommending a chiller, walk the customer through the cheaper interventions, because for many community tanks they are enough: a clip-on fan blowing across the open water surface drives evaporative cooling and can drop several degrees, especially paired with an air pump; floating the lights higher; running lights at night when the room is cooler; and partial cool water changes during a heat spike (Aquarium Co-Op cooling methods; Swell UK). A fan trades water (you top up evaporation) for temperature. When that trade-off is not enough — or when the livestock cannot tolerate the swing a fan still allows — the customer needs a chiller.
A chiller is sized in BTU/hr, from water volume and the temperature drop you need it to maintain against the room. The working formula used across the hobby:
Weight of water (lb) × temperature drop (°F) per hour = BTU/hr load
Practically, that reduces to (tank volume in gallons × 8.34) × desired °F drop = BTU/hr, with freshwater using a factor near 8.3 and saltwater near 8.5 for its higher density (Austin Reef Club sizing formula; Hamza’s Reef calculator).
Worked example from the reef community: dropping a 75-gallon (≈284 L) tank from 84°F to 78°F is (8.3 × 75) × 6 ≈ 3,735 BTU/hr, which a 1/3 HP chiller rated around 4,000 BTU/hr covers comfortably (Austin Reef Club).
The table below converts the formula into a quick reference for a freshwater tank needing a 6°C (≈11°F) drop — a realistic ask for an Egyptian summer room — and a more modest 3°C drop.
| Tank volume | Drop needed | Approx BTU/hr | Typical chiller class |
|---|---|---|---|
| 100 L (≈26 gal) | 3°C (~5°F) | ~1,100 | 1/15–1/10 HP |
| 100 L (≈26 gal) | 6°C (~11°F) | ~2,400 | 1/10–1/4 HP |
| 200 L (≈53 gal) | 3°C (~5°F) | ~2,200 | 1/10–1/4 HP |
| 200 L (≈53 gal) | 6°C (~11°F) | ~4,900 | 1/4–1/3 HP |
| 350 L (≈92 gal) | 6°C (~11°F) | ~8,500 | 1/2 HP |
| 500 L (≈132 gal) | 6°C (~11°F) | ~12,200 | 3/4–1 HP |
BTU/hr figures are calculated from the formula above and rounded; HP classes are indicative because manufacturers rate units differently. Always check the unit’s published BTU rating against the calculated load rather than trusting the HP label alone.
Three sizing rules to pass on:
Innovote Global imports aquatics hardware into Egypt for pet shops and distributors; we source the equipment, we do not manufacture it. For temperature control the shelf logic is straightforward, and it sells through because every tank needs it year-round.
Heaters — stock by the table, not by guesswork. Carry a wattage ladder that covers the common cases: a nano size (around 100 W), a 150 W and 300 W for the bulk of community tanks, and 500 W for larger systems that customers will pair. SUNSUN’s submersible range maps onto this cleanly. The GB stainless-steel series spans roughly 25 W to 500 W with integrated thermostats, the JRB glass series runs 100 W (JRB-210) through 500 W (JRB-250) with an adjustable 20–35°C range, and the EH external/inline heaters cover up to 300 L (EH-300) and 500 L (EH-500) for canister and sump setups (SUNSUN GB series — East Ocean; SUNSUN JRB-230 — Aquanature; SUNSUN external heater — Aquascape Shop). Digital LCD models such as the RS-698 hold ±0.5°C and suit customers who want a visible readout (SUNSUN RS-698 manual). Note these are 220–240V units, which matches Egyptian mains — a genuine selling point against grey-market 110V stock.
Pair heaters with the right safety story. For valuable tanks, stock an external temperature controller alongside titanium heaters; for community tanks, at minimum keep cheap independent thermometers at the till as an attachment sale. Train counter staff to ask the three sizing questions (litres, target, coldest room) so the recommendation fits the customer’s room.
Chillers — stock thin, advise wide. Chillers are heavier, higher-value, lower-turn items. For most shops the right model is to hold one or two common classes (a 1/4 HP and a 1/2 HP cover most reef and planted customers) and bring larger units in to order. Lead with the cheaper cooling interventions — surface fans, lighting changes — and reserve chillers for reef, high-value, and coldwater customers who genuinely need them through Egyptian summer. Specifications, voltage, and BTU ratings on any unit are available on request.
This sits within Innovote’s broader aquascaping range — see the aquascaping hub for how heating and cooling fit alongside filtration and water chemistry, the guide to filter sizing for matching flow to tank volume, and the explainer on the nitrogen cycle, since stable temperature is what keeps a biofilter’s bacteria working.
What wattage heater do I need for a 200-litre tank?
For a typical home where the room drops to within 6–10°C of your target temperature, around 500 W (one 500 W unit, or two 300 W for redundancy if you prefer). In a heated room with a small delta, 300 W is enough; in an unheated winter room, plan for two heaters totalling 700–800 W. Confirm by multiplying litres × delta × 0.5.
Is one big heater or two smaller heaters better?
Below about 300 litres, one correctly sized heater is fine. At 300 litres and above, two heaters splitting the total wattage give more even heat and a safety margin: if one fails off the other holds temperature, and a half-sized stuck heater cannot overheat the tank as badly as a single full-sized one.
Do I really need an external temperature controller?
Not for every tank, but it is the best protection against the most common disaster — a heater stuck in the ON position. For reef tanks and any high-value setup it is strongly recommended. For community tanks, an independent thermometer you actually check is the minimum.
When does a tank need a chiller instead of a fan?
A surface fan can drop several degrees by evaporation and is enough for many community tanks. You need a chiller when a fan cannot hold the temperature low enough or stable enough — typically reef tanks, strongly lit planted tanks, coldwater species, and any valuable tank in an un-air-conditioned room through Egyptian summer.
How do I size a chiller?
Calculate the load: tank volume in gallons × 8.34 × the °F drop you need = BTU/hr. Match a chiller whose published BTU/hr rating meets or slightly exceeds that figure, and give it free airflow. Going one class larger costs little extra to run and copes better on the hottest days.
Are SUNSUN heaters suitable for the Egyptian market?
Yes — the submersible and external ranges are built for 220–240V mains, matching Egyptian supply, and cover the full wattage ladder from nano tanks to 500 L systems. Match the model to the sizing table above; full specs are on request.
Planning a heating and cooling range for your shop or distribution line? Innovote can build a stocking list against your customers’ tank sizes and the Egyptian climate, with specs and pricing on request. Talk to the Innovote Trade Desk.