WOW Thats low PH for tap water. Mine comes out at 7.5 and I wish mine were a tad lower around 6.5-6.8 as I have Discus. Crushed coral to raise....I use drift wood to lower.
It's good your parameters are still OK and a pH of 5.5 on its own will not hurt your rays unless the biological filter quits working. What type of ammonia test kit do you have - does it measure total ammonia or only free ammonia? As long as it's measuring total ammonia you can safely raise the pH.
Half a cup of crushed coral will probably not make any difference, I tried using much more than that and it was unable to contend with the Kh reduction caused by the filter, which is why I've switched to using baking soda.
hereticlosmorte;4653266; said:mine is a steady 8.0 all the time.
the worst part is the hard water stains on the dishes. so irritating.
Just Toby;4650643; said:Oh YES they go out of date...a lot.
They have use by dates printed on them.
Try another kit and if still low you might want to contact the water company...there are legal parameters and something bad could be affecting your water...and you!