Dosing N

[knashash]

My nitrates are at 5ppm pretty much everytime I test for them. Do I need to be thinking about dosing N......every time I think about buying some at the lfs the sales guys advise me against it saying that the bio load should be enough to sustain plant growth.....my plants seem to be doing ok except for a recently nast outbreak of blue-green algae in my 10 gallon....got it under control on my 55 gallon by doing a 3 day blackout.....sorry for rambling...any thoughts?

 

[djlen]

Everything revolves around light. How much are you supplying over your 55?
If 2watts/gal. and under, you may not need to dose anything, depending on fish load and a few other variables.
If 3watts/gal. and over, you probably need to dose, depending on plant mass, what elements you are getting out of the tap etc. In this scenario you need to start thinking about test kits to find out what your tank's parameters are in order to balance light/plants/nutrients.

Len

 

[knashash]

Have got 170 watts over my 55 gallon..putting me at just over 3wpg...heavily planted with DIY CO2...PH is 7.0

 

[djlen]

You will need KNO3, PO4 and a good Trace mix.
Depending on your fish load, you may also need KCl or K2SO4 for potassium. A light fish load and you can add extra KNO3 and not need the K+. A heavy fish load and you may want to dose a bit extra K.
If you have soft water, you might consider dosing some extra Mg and Ca, also available at the below address.
You can get all of them at: www.gregwatson.com/ (feel like I'm doing a commercial for the guy), but it's one stop shopping and reasonable.
Download a good nutrient calculator here: www.csd.net/~cgadd/aqua/articles.htm
Follow the directions the calculator gives you to start and tweak dosages if needed.
You should know the following things about your water: pH,kH,P,N. These should be known(test kits) in tank and what the tap gives you, when you have higher light levels.
Some of the above elements can be obtained close to home and quite inexpensively.
If you're interested we can supply that information as well.

Len