Stage 3 - Substrate Fertiliser

There are various ways you can add fertiliser to the substrate and it is well worth doing so as it will greatly aid the growth of the plants....hopefully!

There are a few options out there and these are the ones we came across.

• RedSea do a pre-mixed gravel in bags. You use this on the bottom layer and then add a decorative gravel on top or you can use their gravel for the whole thing. - This sounds good and an easy way to do things but each bag of gravel costs around $70 and we needed about 3 bags...
  
  
• Dupla do a gravel as well but you have to add the fertiliser to it. The fertiliser is a red clay laterite. You can just buy this laterite and add it to your own gravel. - This is what we ended up doing as it cost $40 and then we could add it to the gravel of our choice

The gravel that we chose was a 2-3mm black granite non-polished. It is best to chose a small grade gravel for the planted aquarium as the plant roots like a fine substrate. Be careful using very fine substrate as they can become anaerobic.

To begin with we washed the black granite gravel thoroughly. This took quite a while as it was very dusty as we had 50 kg to wash. We filled half a bucket with the gravel and filled with water and swished around and drained and repeated about 10-15 times for each bucket.

To add the Dupla fertiliser you take about 1/3 of the gravel and mix in the fertiliser. Use gloves as it is bright red and will stain.

Now add the fertilised substrate to the gravel around the heating cable. We added some gravel

in first to make sure that the cables were not touching. Not sure if this was essential to do or not.

We then added the remaining 2/3 of the gravel on top of the gravel with the fertiliser. We took Takashi Amano's advice and and sloped the gravel from the front of the tank to the back. So that it ended up being about 5 cm thick at the front and 9-10cm thick at the back of the tank. According to Takashi this forces perspective and will make for a more beautiful planted tank.

You can clearly see the layer of gravel with fertiliser. this should become less obvious as the plants begin to grow.