Is it necessary to add an additional nutrient substrate such as JBL AquaBasis under JBL Manado, or do JBL Manado’s properties enable it to do without?
JBL Manado itself doesn’t contain any fertilizer. JBL Manado is, however, able to absorb nutrients (especially trace elements) to supply to the plant roots.
For a good plant growth it is advisable to use JBL AquaBasis plus underneath JBL Manado.
Can JBL Manado be used with a substrate heating cable additionally, or would that lead to overheating?
I don't see a risk of overheating as long as the substrate heating cable is installed properly with the spacers and is not placed directly on the glass pane.
While adding JBL Manado to the tank, we noticed a magnetic component. What is that?
Manado is produced from a natural raw material (clay), which can exhibit slight fluctuations in mineral composition, depending on where it was found. The "magnetic component", which can be traced to iron kernels, occurs in isolated cases, but does not have any harmful effect on tank operation. Quite the contrary, plants need iron as a trace element and use it.
Can I use a gravel cleaner with JBL Manado?
Manado has a lower specific weight than gravel. The substrate can usually be cleaned with a gravel cleaner of sufficient width. If Manado is suctioned with too much force, it helps to decrease the suction power by means of a stopcock, for example.
If a tank has just been set up, normally, the bottom does not need to be cleaned thoroughly, and cleaning can be limited to the upper part of the tank.