Hah! LOL, how did I know.
If I was going to put a bet on one or the other, it would be the rocks from Phillip Island ... from the beach.
How to test? do the vinegar test.
Take out a bit of gravel, and a small stone. drop some vinegar on them to see if you get a reaction.
Alternate test is to put them in a cup of water. Test the water GH and KH before adding, then test again after a few hours to see if KH and GH have increased.
ahh shoot. gravel was washed about 20 times thru, and rocks were boiled. gravel was sold as aquarium safe gravel, but the rocks were from phillip island, along the beach... how could i just test 1 or 2 to see if that's why? (they're all the same type, but i have a few big ones that r heavy and a bunch of small ones that i can test with)
eek! I've been trying to reduce the hardness for a few weeks since i noticed it was high. I'm in melb, and my tap water is relatively soft, but it doesn't seem to make a difference to the hardness when i do water changes. I've been doing up to 40% weekly (on average maybe 30%) but have barely seen improvement... I'm using water that's already at about 23 degrees from tap, would it make a difference if I used just cold? (I've only measured cold tap, not heated as i didn't think it would be different). Otherwise if I could get RO from somewhere would that help?
Those parameters are getting too high for a killi. Killis definitely prefer soft water and slightly acidic, pH under 7.0.
Irrespective of what disease it might have, it would be a good idea to start reducing pH, GH and KH slowly now. Where abouts in VIC are you? Melbourne's tap water is generally very good for softwater fish.
If we can't ID the disease, start with an all purpose cure, like malachite green.