Fishless cycle question

[Donnyreefer]

Hey im just wondering why my nitrates are going down but my nitrites are still up towards 5.0 ppm? Plus my ph is dropping , tanks been up for 5 days and started the cycle with fritz zyme 9 and a piece of raw shrimp . Got my ammonia up to about 3ppm and took the shrimp out , its going through a bacterial bloom and wasnt really sure what to expect when testing . Just confused really lol i appreciate the help
20 gallon long
Dry rock
Live sand
Heat - 78°
Salinity-1.025

 

[Donnyreefer]

Heres a picture of the test 2 days ago

 

[Peter_in_the_city]

The accuracy of API kits is questionable. I don't know if it occurs on a small scale (20 gallon system) but there is another component of the nitrogen cycle where nitrites and nitrates are broken down into nitrogen gas thus reducing concentrations of both (again I don't know to what extent it occurs in a new 20 gallon system). What I think is more likely occurring is just variance in the API test kit.

I don't know your air exchange situation but I would bet the pH drop could be because of CO2 concentrations rising in your tank. Open a window (I don't know where you live and it is the winter so that may not be easy) or if you have a skimmer route the air suction outside of your house.

This is my personal experience but plenty of reefers have similar stories of pH <7.8 and then just route air intake of their skimmer outside and see their pH rise. Regardless I wouldn't worry about pH until you see 0 ppm ammonia and nitrites.

 

[DE FISH]

I’d say it’s perfectly normal as the tank is still cycling

 

[anthonygf]

API has a different chart for salt water. Anyway, if you get 20lbs of live rock in there you can skip the cycle. I did when I started my 46, started the tank with 20lbs live rock and a couple fish and never had ammonia buildup. And then just gradually add more fish and another piece of live rock to go with the fish. Worked great for me, never had a bad ugly stage and going for 5 years.

 

[anthonygf]

As far as the bloom, a small UV light with built in powerhead you can place in the tank will help. Just make sure the UV bulb is internal of the casing, the light is harmful to animals and us to I believe.