Lots of dissolved solids like heavy metals and organic compounds. Something that will either kill your beneficial bacteria or anemone eventually. Get a RODI system or use bottled water to fill your tank. What salt do you use?
I’ve kept a carpet anemone before in a pico tank. Not advisable, but it works if you put 100% effort into it. Having a 10/20g tank may be small, but you will need to test important paras at least every 3 days and top up daily. Run a skimmer/ATO/hang on fuge if you can. From experience, anemones are hardier than people think, but it dosnt mean you can neglect them...
Distilled water is simply super purified water. You can buy or buy the gallon at drug stores and such. Some places have a dispenser so you can use your own container.
You can’t make distilled but a lot of us make “RODI” water which is short for “reverse osmosis de-ionized” water. There are a ton of different RODI units you can buy at places like BulkReefSupply or MarineDepot etc.
Sorry! I don’t watch YouTube videos for much of anything. If you feel comfortable making distilled water then go for it. For me a RODI unit was a no brainer. But I have a 120G tank.
