Tropical freshwater tank

[Twins300822]

Hi I’m new to here and aquariums
We have a 250lt ciano tank
Nitrites were high so did a 25% water change as suggested with RO water from our local aquarium supplier, after testing the nitrates nitrites have gone through the roof
Any suggestions
Thank you

 

[Colin_T]

If you have an ammonia or nitrite reading, it means the filter isn't established (doesn't have enough beneficial filter bacteria to convert the ammonia into nitrite, and nitrite into nitrate).

Reduce feeding to once a day or once every second day.

Do a 75% water change and gravel clean the substrate any day you have an ammonia or nitrite reading above 0ppm, or a nitrate reading above 20ppm.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

 

[GaryE]

The fact the store suggested you use RO water is interesting. Could it be they know there's nitrate in the tap water?

Other British aquarists have talked about that here - I believe from the south of England. The only Poole I know of is in that general region. It might be worthwhile to test a clean glass of tapwater.

Pollution in the tapwater is also an issue in the Midwest, farming regions of the US. People have to handle their water changes differently there ,from what I read here.

 

[TwoTankAmin]

Read here for how to handle nitrite using a bit of salt. it is the best option, IMHO
https/www.fishforums.net/threads/rescuing-a-fish-inIcycle-gone-wild-part-il.433778/

 

[10 Tanks]

Hello. Small water changes don't do much to establish a steady water chemistry which is all your fish really need to be healthy. You have a fairly large tank, so your water changes should large as well. I would focus on keeping a steady water chemistry by gradually working up to the point you're removing and replacing half the water every few days. Gradual changes in the water won't affect your fish. The larger water change will remove more nitrogen and help steady the water chemistry.

10

 

[Essjay]

The OP gives their location as Poole, so I googled a high street bank in Poole and used their postcode on Wessex Water's website. The tap water for that bank has 32.4 ppm nitrate so the OP's nitrate should be similar. Water changes with tap water won't get nitrate below 32 ppm.

 

[Twins300822]

Have completed a 95% water change testing water once up to temperature the putting fish back in

 

[Colin_T]

You shouldn't remove the fish when doing water changes. Just drain the water out and refill the tank. The fish can swim around the bottom of the tank for a few minutes while you fill it back up.