If you have galvanized pipe in your house, you probably have debris in; your water line, your angle stop (AKA cut off),your supply line to the hot side of the fixture. If I could see it, I could tell you how to fix it. I would suggest calling a plumber. We aren't all a bunch of crooks.
You have a leak in your pipes. I know you're probably thinking, how is my hot water getting water then?
I went thru this myself last Thanksgiving. What happens is your water comes in the house and usually splits one pipe to the hot water then the other goes to feed the other cold water pipes. Its somewhere after this split you have a leak, and probably a good sized one. I had to have my kitchen floor ripped up to discover this. it was where two pipes were joined together improperly, eventually the pressure lead to it blowing and boom..no cold water.
Or if galvanized piping it could be full of debris right at the angle/straight stop or the galvanized pipe it self, in rare cases sometimes the faucet supply or faucet it self could be plugged on the cold water side
Milk will probably work fine, if you can keep it cold.
Plecos work well in ponds and cold water aquariums.
water pressure
No cold water will just give you muscle spasms and cramp
As long as it has easy access to a water source, it will work fine.
Salt
no not really hot water cleans better and kills germs
Mine is fine! Yours is where the problem is. There is too little information here to answer the question. Troubleshooting would be to start at the faucet and work backwards until the cause is found. Are we talking water that starts and stops or hot water that runs out and becomes cold?
Yes, it will work. if you live where you have extreme cold in the winter get a battery with the most CCAs you can find. If you live in a warm climate then the 870 CCA will be fine.
On single handle shower valves, designed to let cold water first and turn handle farther to mix hot water to desired setting. If hot water turned on first, possibility of getting scalded. If seperate hot/cold handles for shower, shower valve needs work.
20
All the lights work the voltage is fine and I just replaced the starter. But it registers no CCAs