Your Cart is Empty
Easy Iwagumi in 3 Steps
Iwagumi aquascapes are very popular, anchored by aesthetic rocks in carpets of rolling hills. But 2 common challenges remain:
- How to have clean algae-free rocks?
- How to have a thriving, algae-free carpet?
With the right parameters, Iwagumi aquascapes are surprisingly easy to maintain.
Here are the 3 Steps, the 2Hr Way:
Step 1: 50 PAR
To maintain algae free rocks, adjust the lighting to 40~50 umol PAR (measured at substrate level).
Precision is important here: 66 PAR is not visually different from 50 PAR, but 30% more energy = green rocks.
Note the green algae on the Seiryu rocks at the top right. Incidental light from a neighboring tank increased the light intensity in this zone to 66 umols of PAR, enough for persistent algae growth.
Refer to this earlier post on how to use an iphone App to estimate PAR.
Contrary to the popular belief that carpets require very strong lighting, even ~30 PAR is sufficient for popular carpeting plants: Eleocharis acicularis, Eleocharis parvula, Hemianthus callitrichoides 'Cuba', Utricularia gramminifolia, Micranthemum tweediei 'Monte carlo' etc.
STEP 2: zero N
In our Iwagumi aquascapes, nitrates in the water (NO3) are measured at an average of zero. We use APT1 (complete diet without nitrates and phosphates) to deliberately keep N and P levels close to zero. This helps keep glass and rock free of green dust and other algae.
How does it work? We feed the carpet with a rich aquasoil (APT START for new tanks, APT JAZZ after 3 months). This combination of lean water + rich substrate is a key strategy.
The nitrate level is zero due to the continuous absorption by the plants. It is not necessary to have a positive residual reading to grow plants well. So when we measure NO3 at the end of the day, it reads zero.
Step 3:Vacuum Cleaning
Accumulated detritus (note the "brown dust" on the rocks above) invites algae. Iwagumi aquascapes are particularly susceptible due to the overall lower plant mass (space taken up by sandbars or hardscape). This makes cleanliness especially important.
We perform 50-80% water changes on a weekly (or bi-weekly) basis, taking care to remove accumulated detritus from rocks and the substrate surface.
The humble siphon does a good job of gently stirring up detritus, which we siphon off. For larger tanks, a turkey baster or equivalent can be used instead.
What else?
Spot-dripping APT FIXLITE or APT FIX on hardscape during water change is highly effective in making them sparkling white.
- Drain the tank to expose rocks.
- Spot-drip on targeted areas.
- (optional) Use a paintbrush to cover larger surfaces.
- If you exceed 1ml per 10L of tank volume, fill the tank and perform another 50% water change.
- All carpets become overgrown after some time. This is how we maintain them.
unlock your true potential
Grow anything, defeat algae, create amazing aquascapes
