your not doing a water change at all, because in small tanks that is the most imprtant thing over all others......you could turn off your filter and use a powerhead with hoses attached to both side of the pump and pump the water into that and let the filter catch all the large stuff, and then flow back into the tank..... I know Aquaclear PW's have a flow control switch. .......

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Gold Coast Aquarium Society South Florida
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