Dosing ferts really doesn't have to be a scheduled maintenance weekly with low or medium light energy supplied. After a water change the majority of my tanks are baseline dosed and that's it until the next water change. Plantex CSM+B or Millers Microplex $10 - 12/lb, NO3 $3/lb and PO4 $5/lb are what most using tap for tanking need to be concerned with. Those amounts last a really long time for most folks.
When I change water finishing up I dose NO3, PO4 and trace, not hard at all really.
Plants do have to be fed. Just like you feed the fish you should feed the plants.
Years ago I copied this info from Rex's site and it's the same as all the fert calculators provide today.
1) KNO3 aka Potassium Nitrate is used to primarily dose nitrates or NO3. It does have the side effect of dosing a small amount of potassium.
2) KH2PO4 or Mono Potassium Phosphate is used for dosing phosphates or PO4.
3) Plantex CSM+B is a trace mineral mix.
I mix solutions using 250ml of water in the same glass jars I've used for years. Measuring for tank use is a 10ml syringe (same one for years).
(using measuring spoons you always use level measurements)
PO4 = Mix 1 cup water (236 ml) with 5 teaspoons (24 grams).
This solution will dose 0.93 ppm per ml in 20 gallons of water.
NO3 = Mix 67.2 grams or 12 teaspoons or 4 tablespoons of KNO3 in 250 ml of water and this will give you a solution that will dose 4.34 ppm of NO3 in 10 gallons of water and 2.74 ppm of potassium for each ml dosed.
Less than $20 in dry chem lasts most more than a year so I think it's cheap enough. Done after each water change unless you have high energy lighting that's it until the next tank cleaning.
Keeping the tank "really" clean won't cure algae issues. Less light energy slows things down but for plants even Annibus to thrive they need nutrients.
If all you add is what is listed above at each water change I don't see a real need to test levels. This dosing and the value that results has been verified by many, many folks over the years.
Yea, I appreciate this advice. When I finally buy some dry fertilizers, I am going to have some more questions about this. I hope you don't mind.
Dirt Tank Dosing! Sounds naughty doesn't it? lol