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Showing results for tags 'nitrates'.
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I am in the planning stage of a new RAS. I have been reading my Small Scale Aquaculture book and it has answered a few of my unknowns. It has also raised some new questions. Having had an aquaponics system running for a little over 2 years, I thought I knew what I was getting into. Nope, this is a new game. So, now I am wondering what to use as a bio-filter. Van Gorder suggest that his RBC is the way to go with a 2000 gallon pool, but he uses 2 55 gallon clarifiers. I am thinking of using a 12 ft. (2000 gal.) above ground pool to raise blue tilapia in central Florida. I was planning on using a 55 gallon radial flow filter for the solids, a 150 gallon Skippy filter for the ammonia and nitrites and a separate tank growing duckweed for the nitrates. My main objective is to avoid water changes. What do you guys think?
I was so thrilled with last winter's small experiment with two IBC, 60 small tilapia and 30 square feet of grow beds that I took a big jump, built a 20x40 insulated building and maybe the jump was too big because I don't have any nitrates yet. I have the two IBC, 20 small fish, two small sumps with fiber media in series (20 gallons each) with no grow beds but six 4x8 foot rafts, each with about 60 gallons of water. I just added 15 square feet of media/growbed. All I have growing in the first of the 6 rafts is about 50 lettuce seedlings. They aren't growing. Ammonia is about .8, nitrite 0, nitrate 20, pH 7.5, temperature 80F, lots of aeration. Any ideas? I thought I might isolate the one IBC to circulate with the new gravel growbed, add household ammonium and see if I can encourage bacteria to get to work for me. The gravel bed sits atop that IBC and is flood and drain. I can keep the rest of the system from getting any of the enriched/ammoniated water until I see if it begins to cycle with the addition of the growbed gravel. There are no fish in that IBC; they are all in the other IBC and either or both feed back to the sumps with a solids lifting overflow. Is the problem that I have such a huge ratio of water to the number of small fish?
This may be listed somewhere but I thought I would just ask here. What is a good amount of Nitrates to have in a closed system? How about nutrient lvls? I have a Truncheon nutrient meter and was wondering what a good reading would be concerning CF, EC, or PPM. Right now it reads 8 on the meter. And now that I am getting some changes I need to know what the red flags are concerning too much or too little. My Ph has been coming down too and is at about 7.2. Like to get that down to about 6.8 if possible.