What water test kits do I need for a planted tank?

[cgcaver]

I already have pH, NH4, NO2, NO3 for my fish of course, but I wanted to know which tests are MUST HAVES for plants. Also what are some other tests that are good to have on hand? Please specify which are MUST HAVES and which are optional but good.

 

[TankGirl]

May I assume you have a NH3 test? Depending on what kind of water you have be sure you have a "low range" pH and a "high range" pH test kit.

You ought to get yourself a KH/GH test (must have if you are running CO2), and maybe a phosphate test (pretty good to have, especially if you run into algae problems). That's really about it.

 

[malkore]

yep, TG covered it.

 

[BASSNMAN]

I also use an iron test kit. You can adjust the dose of fertilizers to maintain .1 to .2 iron.

 

[cgcaver]

wait... 1 question:

Why do I need to add Flourish Nitrogen to my tank if my bio-filter produces NO3 already? My fish seem to make plenty of NO3 on their own, way more than 5-10ppm...

 

[BrianNY]

Nitrogen is a macro nutrient to plants. They will consume more than your fish will produce. I didn't believe this until I started testing for it. To know that there is enough N in the water, you want to keep the NO3 between 10 and 20ppm. Can you confirm this Greg?

 

[TankGirl]

Once the plants start growing well you will find you cannot measure NO3 at all, and you have to dose it. When I dose it using dry ferts I shoot for about 5-10ppm.

 

[malkore]

depending on your bio load and plant selections, you may not ever need to dose nitrogen/nitrate. 5-15ppm is the desired range...keeping phosphates at 0.5 - 1.5ppm, basically a 10 to 1 ratio of nitrate to phosphate, at a minimum. Some people go with 20:1 ratio without issues.
The key thing to remember is that phosphate gets you into way more trouble, much more quickly, than a little extra nitrate.

YOu'll wanna dose potassium too, but ther'es no cheap test kits for that. Luckily over dosing doesn't cause algae.
What I suggest is just dose about 15ppm worth after a water change, and then midway to your next water change, dose another 5ppm, up to 10ppm if your plants seem to be struggling.
Use Chuck Gadd's calculator to see how much dry potassium is needed to up your tank by 15ppm.