My fish tank has high alkalinity. Is it safe for fish? How to lower?

Thanks for reaching out about Snow. Chronic high alkalinity and hardness can expose to fish to high levels of minerals that could lead to abnormal mineralization/calcification of gills and other orders. Test your tap water and if also high, which is expected, than bottled water might be in order. Good luck.

I would recommend to have the water completely changed. New water should be ideally submitted for quality testing. Most pet stores will do this for free or a nominal fee. High ammonia levels, PH imbalances may be responsible for that as well. Oxygen concentration and quality of the filters should be determined as well. Please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.

Water conditioning can be complicated and I recommend to stop by your local aquarium store. They are most often familiar with the local water quality and can give recommendations specific to your location. Some areas need buffering solutions to help control things like the water pH. Here are a few links which may help answer some of your questions about water condition: https://www.aqueon.com/articles/freshwater-aquarium-water-quality https://www.petcoach.co/article/aquarium-water-management-alkalinity-vs-water-hardness/ Before moving your goldfish, make sure all the conditions are appropriate for goldfish: https://www.aqueon.com/information/care-sheets/goldfish https://www.petcoach.co/article/how-to-help-your-new-goldfish-thrive/ I hope this helps and please feel free to post any additional questions.

Yes, in order to have a healthy tank and to give your fish the best environment, it is necessary. Here is a good write-up on the reasons why: https://www.petcoach.co/article/water-chemistry-basics-ph-temperature-water-hardness-waste/

Here is a helpful link: https://www.aqueon.com/information/care-sheets/goldfish Your local aquarium store will likely carry a powdered product to add to the water to increase the pH. The package will have dosing instructions. I hope this helps and please feel free to post any additional questions.

Thanks for reaching out. There are many products available in pet stores for either adjusting pH up or down. Adding a buffer as a substrate (dolomite) could help regulate also. Maintaining water quality is obviously very important. Good luck.

Water softeners leave very little salt residue in the treated water. Most, not all, fish *should* do fine in softened water. Make sure you get species that does better in soft water. Use a hardness kit and monitor KH. This parameter is what can affect pH. You can set aside a gallon or two and test it after it has aged for 24-48 hours to confirm it is safe to use. Check the softener unit for a bypass valve. Some units will have one or you can get one installed. Taps/faucets outside may not be in line with the softener, so you can use water from there if necessary.