hard water

hi all I’m looking for some advice on hard water and limescale I have quite hard water where I live and this evening one of my FX6 stopped working when I plugged it in following a water change. Took the motor apart and it’s covered in limescale, I’ve cleaned it all up and it’s now working...

Do Bichir prefer soft, medium or hard water with what ideal PH? I was thinking 3-6Kh with a Ph around 7-7.5? But all comments appreciated.

I’m cleaning up a tank for a friend of mine and am going to paint the back. The only problem is is that there are hard water stains on the back. If I paint the back will the hard water stains mess up the paint?

So I've got a little 29 gal, a whole load of crushed coral sand, and loads of coral skeletons sitting around doing nothing. I'd like to plop the sand and dead coral into a tank, and i plan to keep the aquarium freshwater or maybe brackish. I could do with a little advice on stocking said tank...

Hello, I have a 6gal Fluval edge that is currently salt. Previously it housed a fire shrimp for 2 year. I am debating on switching to a freshwater tank for crystal red shrimp. I have a couple of questions though: 1. the pH of the water here is 7.8...would the shrimp survive even with drip...