pH level of 5??

hi, i have just tested the "run off" water from one of my plants, the result was pH5 compared to the tap water level of pH8! i did the test with my aquarium ph kit so its not going to be 100% accurate but its still acidic. what should i do, try and bump it up to six or just leave it??

make a tea usin lime maybe a table spoon in a gallon or just half to be and test it again tomarrow with clean tap water