The Dutch 90P

Recorded Data

Every figure below is a count taken from the database at page load, not a number typed into the page. Each one links to where the underlying data can be seen.

Project Purpose

This is my 90P Dutch tank, the third layout in it and the first documented well enough that the next version can inherit more than photographs and memory. I document it with measurements rather than impressions. PAR, water chemistry, plant development, equipment changes and operating conditions are tracked over time to better understand what produces healthy growth and strong coloration. The reasoning behind that approach is set out in the measurement philosophy.

The goal is to create a useful, transparent record of the tank’s development, including a controlled comparison between the original ADA Solar RGB and the Chihiros WRGB II Pro 90 that replaced it.

Installed Now

Aquarium

UNS 90P · Dutch-inspired planted layout · ADA Amazonia Ver.2 · rescape started July 3, 2026

Light

Chihiros WRGB II Pro 90, installed September 17, 2026 · R125 G95 B130 W0 · ramp up from 9am, full 9:30am – 3:30pm, off 4pm (schedule copied from the fixture’s app, checked November 1, 2026). The original ADA Solar RGB is out of service and kept as the baseline.

CO₂

Regulator and solenoid into an inline diffuser · a fixed daily window on an Apex outlet, run by the Apex's own program: on two hours before the light, off when it starts to fade. Off below pH 4.70, after a leak and during water changes. Pearling watches it and alerts if it is on when it should be off · not closed-loop on pH; the logged pH drop is used to review and tune the schedule

Fertilizer

2Hr Aquarist APT 3 · 4 mL/day in one dose, dosed automatically by the Red Sea ReefDose 2

Water

RODI remineralized with 2Hr Aquarist APT SKY, 9 g per 20 US gal (11.25 g for a 25 gal batch) · practice, not a measurement: KH kept near zero on purpose; GH generally around 5–6 dGH

Circulation

EHEIM Professionel 5e 700 · ADA Super Jet ES-600 · ADA Vuppa II · AI Nero circulation pump, about 25% by day and 40% overnight, reading 40% now

pH probe

Apera Instruments 203DJ-C on the Neptune Apex, since September 19, 2026. The Milwaukee MA911B/2 is retired.

Measured

Temperature, pH and conductivity logged continuously · PAR measured by hand · water chemistry hand-tested

Background

Clear rear glass, no illuminated background; the room wall is visible behind the tank. The DET panel failed in October 2026 and is out of the tank; it is repairable.

Plants

16 active groups; removed groups stay in the record

Displays

A tablet mounted beside the aquarium showing Pearling · A private dashboard · This public site

Planted Species

The groups in the tank on August 8, 2026, labeled on that day’s photograph with the PAR from the survey taken the same day. Groups moved, removed or added since are listed on the plant index.

01 Vallisneria nana

PAR 196 µmol

02 Lobelia cardinalis 'Mini'

PAR 127 µmol

03 Alternanthera reineckii 'Mini'

PAR 90 µmol

04 Myriophyllum 'Guyana'

PAR 67 µmol

06 Rotala 'Orange Juice'

PAR 125 µmol

07 Rotala 'Blood Red' (as sold)

PAR 165 µmol

08 Limnophila hippuridoides

PAR 136 µmol

09 Pogostemon stellatus

PAR 70 µmol

10 Hygrophila 'Kompakt'

PAR 55 µmol

11 Ludwigia arcuata

PAR 70 µmol

12 Hygrophila pinnatifida

PAR 85 µmol

13 Staurogyne repens

PAR 85 µmol

14 Micranthemum tweediei 'Monte Carlo'

PAR 120 µmol

15 Alternanthera 'Super Magenta'

PAR 75 µmol

16 Ludwigia glandulosa (Peruensis)

PAR 105 µmol

17 Rotala macrandra (FULL)

PAR 100 µmol

18 Ludwigia 'Pantanal'

PAR 135 µmol

19 Rotala wallichii

PAR 100 µmol

20 Rotala macrandra 'Mini'

PAR 130 µmol

Cycle Progress

Fresh ADA Amazonia leaches ammonia for the first few weeks, so a new scape is run on heavy water changes until it stops. Here is that curve, measured rather than assumed, and the tank growing in underneath it.

Hand-tested with a Seachem ammonia alert and a liquid kit. Once this sits at zero across consecutive tests, the water-change schedule can taper off the every-other-day startup cadence.

PAR Measurement Method

Survey

September 18, 2026

Meter

Apogee MQ-510 underwater quantum meter

Measurement type

Underwater PPFD measurements

Fixture

Chihiros WRGB II Pro 90, R86 G86 B95 W15, 7.25″ above the water

Tank format

90P

Measurement locations

15 positions corresponding to plant groups

Sensor position

Held level at the measured plant. Sensor depth recorded per position (6 or 10 in)

Conditions

Aquarium light on, room lighting minimized, water clear

Purpose

Evaluate usable light distribution across the planted layout

• ·Taken the afternoon of 18 September, before that evening's replant, so it describes the layout as it stood that morning.
• ·Fixture height (7.25 in) and sensor depths differ from the Solar RGB baseline, so the two are not a like-for-like comparison.
• ·The channel mix has changed since: R115 G85 B120 W0 from 10 October 2026.
• ·Fifteen positions. Positions 1, 17 and 19 were not measured.

PAR values represent the measured light at each recorded location. They are not universal plant requirements and should be interpreted alongside CO₂, nutrients, plant health, spectrum and canopy height.

PPFD by Plant Position

15 underwater measurements from the most recent full survey under the Chihiros WRGB II Pro 90. The baseline under the original ADA Solar RGB is in the complete survey record. The table compares the measured PPFD at each position with a practical working range used to evaluate whether light may be limiting growth or coloration. A figure quoted for a fixture over open water does not say what the plant in the corner is getting. Measured mid-photoperiod with an Apogee MQ-510 held level at the plant, fixture 7.25″ above the water · September 18, 2026.

Spot checks since

Oct 10 · #14 · Micranthemum tweediei 'Monte Carlo'

55 µmol/m²/s · channels R115 G85 B120 W0

Oct 10 · #6 · Rotala 'Orange Juice'

150 µmol/m²/s · channels R115 G85 B120 W0

Oct 10 · #7 · Rotala 'Blood Red' (as sold)

110 µmol/m²/s · channels R115 G85 B120 W0

Sep 18 · #7 · Rotala 'Blood Red' (as sold)

80 µmol/m²/s · channels R86 G86 B95 W15

Sep 18 · #18 · Ludwigia 'Pantanal'

100 µmol/m²/s · channels R86 G86 B95 W15

Sep 18 · #6 · Rotala 'Orange Juice'

115 µmol/m²/s · channels R86 G86 B95 W15

Single positions measured after a replant or a settings change. They are not a survey and are not drawn on the map.

PPFD by Position, Ascending

Lighting

Experiments

The full experiment archive →

Current Conditions

CO₂ goes in through an inline diffuser on a fixed daily window that follows the light, switched on a smart power strip with a pH floor and a safety timer on the strip itself. Pearling logs pH continuously and the day’s drop is used to review and tune that schedule; it is not closing the loop on pH. Closed-loop control was built and tested earlier and is switched off. The drop is read as an operational signal rather than an absolute dissolved CO₂ measurement: at near-zero KH the pH/KH table does not apply, so no ppm figure is published here.

Dissolved solids climb as the tank consumes and evaporates, then drop sharply at each water change. Every sawtooth in this trace is a ~53% change. Tracking the creep is what sets the change schedule, rather than a fixed calendar.

Water chemistry · hand-tested with liquid kits

KH

0 dKH · 88d ago

GH

6 dGH · 88d ago

TDS

103 ppm · 133d ago

Ammonia

0 ppm · 96d ago

Measured values above, each with its own date. Practice, which is not a measurement: RODI remineralized with 2Hr Aquarist APT SKY at 9 g per 20 US gal (11.25 g for a 25 gal batch). KH kept near zero on purpose; GH generally around 5–6 dGH. Near-zero KH is the intended state on this aquasoil, not a fault.

Hardware and Software

Setup

Product names match the live inventory that runs this tank. Linked items have a documentation page covering why they were chosen and what has been observed using them.

Measured and logged with Pearling, the self-hosted software that monitors and runs this tank. Live figures updated Nov 5, 4:41 PM CT.