What we should know about liquid fertilization?
Very simple… We need to divide the subject in 3 parts; measure the levels of nutrients choosing the right tests, use a good liquid fertilizer with nutrients required by plants and find the balance between nutrients vs CO2 and Lighting.
PART1: Choosing the right tests
What really makes me some confusion is when I talk with somebody about planted aquariums and maintenance, they refer that are using powders to fertilize their aquariums without knowing what are doing… They read somewhere that for keeping aquatic plants in aquarium need phosphorous, nitrates and potassium; basis nutrients as known by NPK. It is too scary listen those people saying that dose 20ml daily of each or even more, depending on the size of the aquarium… but the plants really need such quantity of liquid fertilizer? Unless the concentration of each liquid fertilizer is too small that can permits to add to the water’s column what I usually call of Water’s fertilizer; 98% of water with 2% of nutrients! But this is not a problem, the main problem is they are doing that without knowing the measures because they don’t use tests and when they have it, don’t have the right ones. Please don’t make confusion with NO2 and NO3, both began with the letters “NITR”, but one is Nitrites and other is Nitrates.
To keep a planted Aquarium you will need several tests like PO4 (phosphates), NO3 (nitrates), gH (general hardness), kH (carbonate hardness) and pH (acidity test).
Do we need all of them?!
If you want to keep and know what is happening with your aquarium, you should have them and not wait too long to make some tests when something really happens. Usually I compare this with insurances; people that have them are always complaining about the money that spend with them without taking any benefit, until someday when something happens, they regret for don’t have it or gave up because they didn’t need it.
Tests are more or less the same, we can have them for a long time without using them, but when the plants get algae, are doing meltdown or weak, some fishes start dieing… something is not right; and if you can take care of the problem as soon as possible, better for the healthy of your plants and fishes.
And what about strips tests, are they good?
The strips tests and even some drops tests aren’t too good… to have an idea of the measure values they are nice but not good because most of the time give us different values even when you do it 2 or 3 times in a row.
I remember one time that I was doing a maintenance at one planted aquarium that was full of algae and the test used gave nitrates always above 25ppm. I will not reveal the brand, but I can assure that I will never use or recommend that to a friend or customer. On that tank we have done several water changes waiting that NO3 get normal values or stay near of zero without success. We tested the tap water and the values of NO3 were really high, finally we discover the problem; it was the tap water… or not, because this is not the end of the story! This situation was so strange because the plants stopped growing and all the nutrients were there; The aquarium was well equipped with CO2 and Lighting, no visible reason for that. It was when I remembered to use a different test from other brand; surprisingly the water wasn’t NO3 at all!!!! Not satisfied, I used my own tests and the water of the aquarium and tap water were free of Nitrates… The plants were plenty of algae because of a lack of nutrient and not excess.
If this happened to me and I was using tests (the bad tests on the beginning), I really don’t understand how people can keep a planted aquarium without them.
You can see if a test is good or not when you do several tests in short period of time; if the results are different from one test to another, those tests are nice to have an idea but not good to have precise values. Having 10ppm of nitrates is not the same of having 20ppm.
The ELOS NO3 test Kit is precise and unique on the market. You can measure the nitrates of your aquarium in a scale of 1ppm~25ppm (1-2.5-5-10-25ppm); to do the test you only need to use 5ml of water into a vial, measure spoon of 0,15ml of Reagent A and 6 drops of Reagent B; very simple and easy!
Tests of gH and kH are really needed?
Any planted aquarium that uses argyle as a soil, wood and CO2 usually the water change a little bit his own properties. It become more soft and sometimes we have big surprises.
General hardness gH is what distinguish from soft to hard water, because the results of the hardness depends of the quantity of Magnesium and calcium dissolved on the water. Aquatic plants grow faster if we have soft water around 4~8º; the availability of calcium and magnesium are enough to avoid lack of nutrients and in case of lack, we can simply add Trace elements on the water to solve the problem. When the hardness is too hard, I’m not refering to values between 8~14º but even higher, this problem can be solved using RO Water (reverse osmosis) during water changes. I have been noticed that some plants likes a little bit hardness, in some situations raise the values to 10~15º will enhance the coloration and the way how the plants grow. Stem plants will grow or expand more on horizontal and will be kept for more time below the lighting, enhancing their colouration and get more reds. Increasing the hardness will also increase the difficult on keeping the planted aquarium, because if they don’t grow so fast as before, we need to control again the routine fertilization.
To raise the values of gH, I recommend the use of ELOS Rigenera because contains the right proportion of Calcium and Magnesium.
Carbonate hardness kH needs to be above 3º to have a stable aquarium, otherwise the water can be very acid and we have a big problem for plants and fishes because pH goes down very quickly and could pass from 7 to 4 without you noticed that. Some plants start doing meltdown and disappear from the aquarium; please don’t make confusion with cryptocorynes. This plant can simply do a meltdown when some parameters oscillate, don’t panic because in a few days (2 weeks) will born again. The general meltdown of some plants (not cryptocoryne) can result from the high acidity of the water. In case of you need to raise carbonate hardness of the water you can use Kh+ (buffer) slowly to avoid great oscillation of water’s parameter.