ADA Power Sand Advance Size:S - 2L they definitely need to be

they definitely need to be replaced

Velcro for easy use and re-use

when the excrement of the fish creates excessive nutrient pollution in the water

Higher temperatures cause more activity which requires more food

This in turn leads to an enormous oxygen consumption by the bacteria (nitrification) and to the release of the nutrients nitrate and phosphate

ADA Power Sand Advance Size:S - 2L they definitely need to bePower Sand Special will be switched to POWER SAND ADVANCE. This product has more nutrients than POWER SAND BASIC, and on top of Bacter 100 and Clear Super, it contains BC powder (bamboo charcoal powder), which helps encourage the growth of plants. Choose an appropriate granule size (Small, Medium, Large) based on depth of aquarium water in your tank. 2 liter and 6 liter bags are available.