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fishless cycling PH still to high

I am pretty new here and have been cycling my system without fish. My ph has been high 8.4 since I started and have been adding ph down (sodium bisulfate) approximately a pound in the last 2 weeks. I have about 400 gallons of water in the tanks and i got it down to 8.2 but that is as far as it will go. I got a little careless with the ammonia and that is about 6.0 ppm at this time and I just started getting nitrites and nitrates to show up on the test. Todays readings are as follows:

Water Temp. 62 F

Amm. 6.0 ppm

PH 8.2

nitrite 2.0 ppm

nitrate 10 ppm

Should I continue trying to bring down the PH before I add any plants? Should I try something else to bring down the PH or should I just wait it out for a little while? Are certain plants better for a new system than others? I have read that I should stay away from tomatoes for a couple of months. I will definately wait to add fish until things get better.

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Permalink Reply by TCLynx on April 4, 2011 at 5:08pm

I'm a little concerned about the sodium levels from your attempts at pH adjustment. I don't know much about sodium bisulfate.

Also, what is your media? Might be time to see if your issue is actually your source water of if your media is messing with it. Limestone, marble, or shells as media just won't do, you won't be able to get the pH down consistently until it dissolves away. My well water comes out around 8-8.2 and using pool acid which was sulfuric acid I was able to bring the pH down to about 7.6 after a few doses which was on the order of several spoon fulls of the granulated stuff in my 300 gallon system.

At this point though, you probably want to avoid messing with it and just leave things alone till your ammonia and nitrite come down, if your media isn't messing with the pH, it will probably fall on it's own soon.

Avoid plants that want a low pH (like strawberries and blueberries) for now. Otherwise go ahead and get some plants going as you have enough nitrates for them now. A variety of things appropriate to the upcoming season where you are so you can see what you like and what does well for you. Keep in mind that many things struggle the first year but will do better in future seasons.

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Permalink Reply by Steve Federwisch on April 4, 2011 at 6:20pm

I am using Hydroton as a growing media. I used tap water which is city water for the majority of the water but I used about 60 gallons of local lake water that I tested at 8.2 PH. I will keep monitoring and leave it alone for a couple of days and see what happens.