My Iwagumi Aquascape Journey Part 2: Grow Out



In Part 1, I detailed the beginning of my journey from an idea to a flooded and cycling Iwagumi style aquarium. In part 2, I will cover what I've done since flooding the aquarium. I performed numerous water changes, countless parameter tests, light and flow adjustments, and trimmings.


My goals were to have a beautiful aquarium and learn all I could about this aquascaping style. There were only a few things I would have done sooner If I could do it again, but so far, nothing I regret.


The final leg of the journey will be adding livestock, which I'll discuss in part 3. For now though, let me show you what I've managed so far.


Water Changes

After the flooding, I waited 24 hours and did a water analysis for ammonia (NH3), ammonium (NH4+), nitrite (NO2-), nitrate (NO3-), pH, carbonate hardness (KH), and general hardness (GH).


5/6/22 - 4:00 pm - No Water Change

pH

6.2

KH

0 dKH

GH

3 dGH

NH3/NH4+

8+ ppm

NO2-

0.25 ppm

NO3-

5 ppm

CO2

9.3 ppm

I expected the free and total ammonia to be high because nitrogen leaches from the soil readily at first. However, I did not expect it to max out my test kit at over 8 ppm. I added 1.5 grams of alkalinity (KH) buffer directly to the tank and did not perform a water change.


5/7/22 - 5:00 pm - 1st Water Change

pH

6.0

KH

2 dKH

GH

N/A

NH3/NH4+

8+ ppm

NO2-

1 ppm

NO3-

10 ppm

CO2

59 ppm

The nitrogen cycle is in full swing, there was no sign of algae growth after 48 hours. With some alkalinity in the water, CO2 shot up to 59 ppm at 1.0 bubbles per second. I added 3 g of KH buffer and 3 g of equilibrium (GH buffer) to the 4 gallon water change I performed.


5/8/22 - 4:00 pm - No Water Change

pH

6.2

KH

2 dKH

GH

3 DGH

NH3/NH4+

8+ ppm

NO2-

1 ppm

NO3-

10 ppm

CO2

37 ppm

On day three, I did not perform a water change. I added 1.5 g of KH buffer directly to the tank (after dissolving in a ½ cup of tank water). I increased CO2 to 1.25 bubbles per second.


I measured bubbles per second, by starting a stopwatch and counting bubbles for what felt like about ten seconds. I then stopped the timer and divided the bubbles I counted by the seconds displayed on the watch. I say what “felt” like ten seconds because you don’t want to look away from the bubbles you're counting to check the stopwatch.


If you count 18 bubbles and the stopwatch reads 13 seconds, that's 1.38 bubbles per second. The longer you count, the more accurate your calculation will be.


5/10/22 - 5:45 pm - 2nd Water Change

​pH

6.0

KH

2.5 dKH

GH

3 dGH

NH3/NH4+

8+ ppm

NO2-

5 ppm

NO3-

30 ppm

CO2

73 ppm

The nitrogen cycle is beginning to peak with nitrites at 5 ppm. I added 2 g of KH buffer and 3.2 g of GH buffer to the 4 gallon water change.


5/13/22 - 5:00 pm - 3rd Water Change

pH

6.2

KH

2.0 dKH

GH

3.0 dGH

NH3/NH4+

8+ ppm

NO2-

5 ppm

NO3-

5 ppm

CO2

37 ppm

On day 8 and water change three, I add 3 g of KH buffer and 3.2 g of GH buffer to a 4 gallon water change. No algae and the hair grass is growing rapidly.


5/15/22 - 4:00 pm - 4th Water Change

pH

6.2

KH

3.0 dKH

GH

5.0 dGH

NH3/NH4+

8+ ppm

NO2-

5 ppm

NO3-

5 ppm

CO2

56 ppm

Another water change with 1.2 g of KH buffer and 3.2 grams of GH buffer added to the 4 gallon water change.


5/17/22 - 1:30 pm - 5th Water Change

​pH

6.2

KH

2 dKH

GH

5 dGH

NH3/NH4+

.25 ppm

NO2-

5 ppm

NO3-

5 ppm

CO2

37 ppm

Finally, the ammonia drops to .25 ppm. I completed a 5th water change with 1.5 g of KH buffer and 3 g of GH buffer added to a 4 gallon water change. I also added a half dose (0.5ml) of Flourish, an all in one plant fertilizer.


5/19/22 - 6:20 pm - No Water Change

​pH

6.2

KH

2.0 dKH

GH

6 dKH

NH3/NH4+

0.1 ppm

NO2-

0 ppm

NO3-

50 ppm

CO2

37 ppm

The nitrogen cycle is almost complete. I added another half dose (0.5 ml) of Flourish and 1.5 g of KH buffer directly to the tank. There is calcium and magnesium in the fertilizer. If the plants are not absorbing it fast enough, this may explain why the GH is increasing.


5/22/22 - 4:30 pm - No Water Change

​pH

6.2

KH

3 dKH

GH

6 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

80 ppm

CO2

56 ppm

The nitrogen cycle is complete and nitrate continues to rise.


5/27/22 - 3:00 pm - 6th Water Change

pH

6.4

KH

2.5 dKH

GH

6 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

80 ppm

CO2

73 ppm

PO4+

0.00 ppm

Phosphates tested at 0 ppm. Performed a 4 gallon water change with 1.2 g of KH buffer and 4.2 g of GH buffer added.


6/12/22 - 2:00 pm - 7th Water Change

​pH

6.4

KH

3.5 dKH

GH

6 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

N/A

CO2

41 ppm

Waiting two weeks between water changes to allow plants to soak up as many nitrates as they could. I continued to dose 0.5 ml of Flourish twice weekly. Performed a 4 gallon water change with 1.2 g of KH and 3 g of GH buffer.


5/8/22 - 4:00 pm - No Water Change

pH

6.4

Kh

3.0 dKH

GH

8 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

80 ppm

CO2

35 ppm

Continuing to dose fertilizer without a water change increased GH to 8 dGH, higher than I would like. Performed a 4 gallon water change with 1.2 g of KH and 2 g of GH buffer added.


5/8/22 - 4:00 pm - No Water Change

pH

6.4

KH

4 dKH

GH

6 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

N/A

CO2

47 ppm

4 gallon water change with 1 g of KH and 2 g of GH buffer added.


5/8/22 - 4:00 pm - No Water Change

​pH

6.4

KH

6 dKH

GH

10 dGH

NH3/NH4+

N/A

NO2-

N/A

NO3-

N/A

CO2

118 ppm

After a month of no water change and just adding Flourish twice weekly, the general hardness climbed significantly. I suspect this is the case because the calcium and magnesium is not being utilized by the plants quickly enough and is building up.


I will counteract this with weekly water changes to “reset” the unutilized fertilizer elements. In addition, I will switch to a regimen of adding each fertilizer (nitrogen, phosphorus, potassium, iron, and trace elements) separately. This way, calcium and magnesium levels will be controlled with GH buffer and will not be added by any other source.



Light Adjustment

I’ve adjusted the lighting on this setup three times so far. With a programmable dimmer installed on a Twinstar light, I’m able to ramp up and down the intensity and timing easily.


First Setting 5/6/22

Setting Number

Time (24hr)

Intensity

1

11

1

2

12

20

3

14

50

4

16

50

5

18

20

6

20

10

7

21

5

8

22

0

This first setting was intended for low intensity as the tank was cycling. It was just enough for plant growth, but was intended to keep algae from taking over.


Second Setting 6/23/22

Setting Number

Time (24hr)

Intensity

1

11

1

2

12

20

3

14

50

4

26

60

5

18

60

6

20

20

7

21

10

8

22

0

After the initial tank cycle was winding down and I had started the first fertilizer regimen, I increased the lighting to a higher intensity.


Soon after, I began to get a little hair algae growth. After it subsided, I increased the lighting intensity once more to the third and current setting.


Third Setting 7/10/22

Setting Number

Time (24hr)

Intensity

1

11

1

2

12

20

3

14

50

4

16

70

5

18