OASE HeatUp heaters are available in 25w, 50w, 75w, 100w, 150w, 200w, 250w and 300 watt versions. As an approximate guide, we would suggest a minimum of 1 watt of heating per 1 litre of tank water (i.e. a 50 litre tank would be best suited to a 50w heater).
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