Have a Zoeller battery backup system 585-0005 installed by first home owner
in 4/98. Have 2 connected sumps. First pump going strong (thank God) in flood riddled Chicagoland. Backup pump is weak and rarely goes on (not an alternating system). Battery is a 2 year old Interstate 27 Marine /RV type that took a half gallon of distilled water yesterday. Today the charger has only the red light lit (green and yellow are out) and is only putting out 5.5 volts which is what the battery also reads. Please advise next steps.