cannot see a problem if it was a couple of days ago do you need to adjust the ph up or down? has the ph been stable for a long time or is it a new set up?.if the water is going acidic then i suggest adding bicarb of soda about 1 heaped tea spoon per 100 litres should do it.
yeah the ph has been stable for a while, im wondering if it was the tap water that has changed for some reason. i have a big piece of rock in my tank that naturally levels the ph to about neautral, i have had it a while and wondered whether or not it have kind of expired, so i went and bought a new piece last night to try and level the ph out without adding any chemical things.
