Water samples from home filters in nine residential areas of a Nigerian university community were studied. The membrane filter technique was used to determine the total coliform and faecal coliform counts/100 ml of water. Most of the 100 samples studied were grossly contaminated with total coliform counts/100 ml ranging from 0–442, faecal coliform counts/100 ml, 0–216 and the total aerobic plate count per millilitre ranged from 3·0 × 103 to 1·9 × 109 c.f.u. The source (dams) of water, fitness of filter candles, frequency of cleaning candles and pH of water did not significantly (P > 0·05; X2) affect the microbial quality of either filtered boiled or unboiled tap water.
Escherichia coli type I was isolated from 17·9% of the faccal coliforms tested but from only 2·3% of total coliforms. Enterobacter aerogenes was most predominant (38·5%) amongst faecal coliforms isolated while Enterobacter cloacae was the most frequent (37·2%) of the total coliform isolates.
The gross contamination of filltered water from all households sampled calls fpr am englightenment of residents on the proper use of home water filters.