New tank query - follow up

[Teena]

I’ve been doing a fishless cycle with Tropica aqua soil for just over 4 weeks. Water chemistry is now:
Ammonia 0 (more accurately 0.035ppm)
Nitrite 0.25
Nitrate 5.0

pH fluctuates but after water changes appears to settle at around 7.8-8.1. I live in a hard water area and KH test was around 15 dKH (15 drops in the NT lab test kit)

I’ve been doing water changes every 2-3 days so I never let the ph go above 8.3.

Do I need to do anything to adjust pH and kh levels before I add fish. Understand that I still have some time before I finish cycling as need to get nitrite to 0.

 

[dw1305]

Hi all,
That looks good, can I recommend a floating plant as well <"What is the “Duckweed Index” all about?"> and / or <"Using stem plants as a filtering aid at Start Up!">.

Do I need to do anything to adjust pH and kh levels before I add fish.

Because <"you live in London"> you can only really lower pH and dKH levels with <"rain or RO water">. It is just an <"effect of geology">.

Understand that I still have some time before I finish cycling as need to get nitrite to 0.

Yes, you need nitrite (NO2-) levels at zero. You can test for NO2- <"relatively easily">, but I like <"grown in = fish safe">, there isn't any ambiguity about it.

Have a look at <"Correspondence with Dr Ryan Newton - School of Freshwater Sciences, University of Wisconsin—Milwaukee">, it gives some background to what processes actually occur during "cycling".

cheers Darrel

 

[Teena]

Because <"you live in London"> you can only really lower pH and dKH levels with <"rain or RO water">. It is just an <"effect of geology">

Thanks Darrel, helpful as ever. Can I clarify though, is it ok to leave pH as it is or is it necessary to lower it so that it stays 7-8? My sense is that it's better to aim for a stable pH rather than one that fluctuates.

 

[dw1305]

Hi all,

Can I clarify though, is it ok to leave pH as it is or is it necessary to lower it so that it stays 7-8? My sense is that it's better to aim for a stable pH rather than one that fluctuates.

You have to leave pH where it naturally resides.

Various <"unscrupulous vendors"> will try and sell you pH buffers etc., but <"they are pointless">.

The carbonate buffering will naturally damp down <"pH variation">, but that damped pH value will always be well above pH 7.

Cheers Darrel