Hydroponic grow rooms rely on activated carbon filters as the most efficient way of purifying extracted air to eliminate unpleasant odours. Unlike absorption, these filters employ adsorption, which means that odour-causing molecules cling to the activated carbon without the filter expanding in size. Similarly, as a sponge can only hold a certain amount of water before reaching its limit, carbon filters eventually become saturated with odour-causing molecules, unable to extract any more from the air.
However, the adsorption quality of carbon allows heavier molecules to replace lighter ones, releasing the lighter molecules into the atmosphere. For growers, this indicates that odours will become detectable from their extraction ducting before the filter has reached its useful lifespan - this is referred to as the "breakthrough point." Top-tier carbon filters, such as Phresh and Can-Filter models, have significantly longer useful lives than competing brands, while also more efficiently trapping odour-causing molecules, leading to a later breakthrough point. Users of these premium filters can be confident that their extraction air will remain odourless until the time comes for a new filter.
