Automatic fertilizer doser
In September, I increased the potassium and phosphorus fertilizers’ dosage by 50 %. Also, I started supplying iron using the Seachem Flourish Iron fertilizer. The fertilizers’ application started to be more difficult. I decided to buy a fertilizer dosing unit Aqua Nova NMDP-5. The price was 2970 Kč (US$ 130).
This unit allows the dosage of up to five fertilizers. It is connected by air hoses. To fix the hoses on the aquarium edge, I used the Sera hose holder. My aquarium had only space for four of them. I put the fifth hose under two of the holders. The holders’ package costs 116 Kč (US$ 5) and one package contains two.
The fertilizer dosers have to be calibrated prior the use. The ends of the hoses are located above the water in the aquarium. First, I left the output ends freely above the water surface. However, they used to drip after dosing and some air got into the hoses. So, I put plastic air tube connectors to the outputs. The connectors have smaller apertures thus the fertilizer does not drop. I put the plastic L-type connectors to the inputs, so the fertilizer suction was from the bottle’s bottom.
I programmed the dosar as follows:
| Fertilizer | Frequency | Dose |
|---|---|---|
| Easy Life Fosfo | 3x daily | 2 ml |
| Easy Life Kalium (Potassium) | 2x daily | 2 ml |
| Seachem Flourish Excel | 1x daily | 1 ml |
| Seachem Flourish Iron | 1x daily | 1 ml |
| Seachem Flourish Nitrogen | 1x daily | 1 ml |
Some fertilizes contain air bubbles which are accumulated in the hose. It is necessary to bleed the hose from time to time. Concerning the fourth doser, sometimes the fertilizer slowly returns to the bottle. It seems the doser leaks when in certain position. After all the unit works well.
In the same time the bomb ran out of CO2. When I disconnected the hose, I found out that the bubble counter has cracks along the sides. Probably caused by the pressure. I preventively bought a new one in the Sklorex store. They recommended me a more robust type JBL ProFlora for 315 Kč (US$ 13).
The plants in the aqurium are growing well as one can see in the video. On www.rostlinna-akvaria.cz I bought plants: Proserpinaca palustris Cuba and Cryptocoryne nevillii. The former grows well. The latter was the in-vitro kind and when I opened it, the plant didn’t have roots and the leaves were decaying. So it didn’t last for long.
