New Starter - Fish Advice

One thing you need to buy very soon is a testing kit. Master test kits are cheapest and they usually contain pH, ammonia, nitrite and nitrate. Get liquid reagent testers rather than strips.

https://www.nwl.co.uk/your-home/your-account/your-area.aspx
Look for nitrate in the water quality report.
My mean nitrate is 2.215 ppm - it shows up in the API nitrate test as over 0 but less than 5.


Liquid nitrate testers have a reagent in one of the bottles which does not dissolve. It settles out on the bottom of the bottle. All brands have this, and the instructions will say to shake this bottle before using it and to shake the test tube after you add the reagent. This shaking is very important as it disperses the insoluble chemical evenly throughout the liquid. It is recommended to shake the bottle even longer than it says to.

That's great from a fish point of view because it will be easy to keep it below 20 ppm. Some people have 40 + ppm in their tap water. It has become known in the last couple of years that if tank nitrate is above 20 ppm, the fish don't live as long. Nitrate is not as toxic to fish as ammonia and nitrite, but it is not harmless in levels above 20 ppm.

But from the plant point of view, that might be a bit on the low side. I'll leave it to Matt to answer that.

Will do, thanks for all of the great advice I have received in such a short space of time , I have learned so much!!!

It is a more recent finding, that fish do better with large weekly water changes. A lot of people reckon we should change 75% a week 

The only time I now see small water changes recommended are with shrimp only tanks, and even then it's a small water change more often that once a week. And shrimps to not have the same bioload as fish.


It used to be said that you only needed to water changes as big and as often as necessary to stop nitrate going up by 20 ppm between one water change and the next. We now know that 20 ppm is bad for fish, so if tap water had more than zero nitrate, this regime would push nitrate over the critical level.
And of course planted tanks can't use this guideline anyway as the nitrate above tap level in non-planted tanks comes from ammonia excreted by fish which live plants promptly take up leaving virtually no ammonia for bacteria to turn into nitrate.



Yes, 50% water changes are time consuming if you use a bucket like I do. And especially as we have the type of hot water system with a cylinder in the airing cupboard so I can't use hot tap water to warm the new water. At this time of year, mains water is so cold it takes forever for the kettle to boil 1.5 litres.
You can use a hosepipe to remove the old water, and just have the pipe going out of the window. And with a combi boiler, you can use hot tap water if refilling with buckets.