120 gallon water test

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Aquarium Advice Apprentice
Feb 5, 2011
Ormond Beach Florida
My tank has been running two weeks now with live sand, about 20 pds of lr and a protein skimmer running. These are the results of my first water test.
According to my readings I have:
Ph 7.6
Ammonia 0
Nitrite 1 or 5?
Nitrate 0


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    first water test.jpg
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What did you add to the tank to start the cycle?
You need a source of ammonia first. That could be pure industrial strenght ammonia with no other ingredients that you get at the hardware store, or it could be a few fresh cocktail shrimp you get at the fish store or supermarket.

What is the SG of the tank (please use a refractometer for the reading). The pH is low, which is fine if the tank was cycling and had the correct SG. Otherwise you may need to add some salt mix.
There has been a Damsel in the tank for a week now. He isn't stressed and eats flake.
I saw a mini bristle star this morning..I presume it came from the lr I had purchased.
My SG is within range to the lower side though. I have been measuring the SG with an hydrometer.
With one Damsel the cycle might take a while since your tank is big. You can "accelerate" the cycle with raw shrimp. Do you have a tank you could keep the fish in while the 120 cycles?
Your PH is way too low, raise it to 8.3.
Amonia does not look like zero based on photo, it looks like there is still some in the tank.
There also looks like some nitrite and a little nitrate.
You have not gone through a nitrate spike yet, so more cycling is needed - especially with only 20 lbs of rock.
I have a 120 g also and I cycled in about 6 weeks without using fish. Some folks on the site will give you great grief for cycling with a fish in the tank. I cycled my first saltwater tank, mostly because I did not know any better, with fish and another tank without - there are critics on both sides and experts who really dont think it matters so much and do not classify as 'inhumane'. Again, you get some finatics (excuse the pun) who think your Michael Vick or someone subjecting pets to a dog fight so just recongize there is some anger out there from some when you talk about cycling a tank with a fish or two. I am not promoting the idea of cycling with a fish, but I wont criticize you for it either.
Thanks for the advice everyone. I will probably be taking back the damsel to fish store tomorrow and throw in two uncooked shrimp?
How long should I wait to start testing water after the shrimp are added?
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