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PH & Nitrate Problem/Question

My PH is constantly dropping under the 5 mark in my API test. I add PH Up and it will go up to 6.4 or 6.6 and then four hours later it is back under the 5 mark.

Any idea what is happening?

I also noticed that I will get a zero reading for Nitrates but when the PH goes up I get nitrates again.

I know PH dropping is normal...but in 4 hours? That doesn't seem normal?

How can I keep the PH at a place where the nitrates are continuing to be present?

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Permalink Reply by Keith Rowan on August 2, 2013 at 6:38am

low ph will interfere with (if not completely kill off) the bacteria that cycle the system, that's why your reading will change..

what is the media you are using? what's your water source? what are you cycling with (ammonia source)?

i have used builders lime to raise my ph (by adjusting top up water), and put shellgrit, and lots of ground up eggshells in my growbeds...

do you have an aerator? all parts of the system - plants, fish and bacteria - benefit from having as much dissolved oxygen available as you can give them

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Permalink Reply by R.K. Castillo on August 2, 2013 at 5:32pm

My system was previously cycled. So I have tilapia in my fish tank. One bed has hydroton, the other has black cinder.

I usually use the city water and let it sit in the sun a couple days to gas off any chlorine.

I do not have an aerator.

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Permalink Reply by Keith Rowan on August 3, 2013 at 9:00am

this happens all the time.. a system cycles.. due to the nitrification process, it gradually becomes acidic (ph drops),,

ph crashes, and bioactivity can cease completely, so basically cycling has to start over..

treat your tap up water with hydrated lime in small amounts to gradually increase the ph

add an aerator

ammonia/nitrites will be rising until the system starts cycling again, so go easy on feed and monitor