Power & Supplies
A running farm draws two external inputs: power for grow lamps and supplements for fruiting crops.
Two supply axes
| Axis | Source | Touches a cargo hold? | How you refill it | What it gates |
|---|---|---|---|---|
| Power (light) | ammo.drive_cell from the host's GENERAL hold | Yes, the only hold draw | Auto-drawn while cells sit in the hold | Grow-lamp brightness → growth of all crops |
| Supplements (P/K/Fe) | A persisted dosed pool on the system | No | Right-click the Console holding a supplement item | Only fruiting crops |
Drive Cells are the only thing aquaponics pulls from a cargo hold. Supplements live in the dosed pool; eggs and harvested produce pile up in the system's output buffer and are collected at the Console.
Power: grow lamps burn Drive Cells
Grow Lamps (SEA_LANTERN blocks) light crops, burning Drive Cells (ammo.drive_cell) drawn automatically from the host's shared GENERAL cargo hold.
A fish-only build has no lamps and draws zero power.
How the draw works
Lamps spend cells fractionally; a hold hands out whole cells. A per-farm energy buffer bridges the gap: every couple of seconds the system pulls one whole Drive Cell from the GENERAL hold if the buffer is low (at most one cell per pass), and lamps spend out of that buffer fractionally. An empty hold drains the buffer to zero within a minute; the lamps go dark. A server restart forgives at most the one cell of buffer charge.
The burn rate
Standard numbers (server-tunable):
| Value | Meaning |
|---|---|
| 0.1 cells / lamp-unit / min | Cells burned per lamp-unit per minute |
| 2.0 lamp-units per bed | Lamp output a planted bed wants for full light |
Total burn = total lamp output × 0.1 cells/min. A 2-lamp farm burns ~1 Drive Cell every 5 minutes while online (2 × 0.1/min = 0.2 cells/min). Burn scales linearly with lamp output.
Lamp reach and placement are in Building a System. Lamps only burn while a faction member is online; see The Nitrogen Cycle for the online-gating and grace window.
How an empty hold dims the lights
Light enters crop growth as a multiplier of two pieces:
- Coverage: lamp-units per bed (2 per planted bed for full coverage). Structural.
- Powered fraction: 1.0 with cells in the hold; collapses toward 0 when the hold runs dry and the buffer drains.
Light multiplier = coverage × powered fraction. Refill the hold and the powered fraction returns to 1.0.
Drive Cells also power circulation
Powered circulation pumps (Circulation Relays) only oxygenate while at least one Drive Cell is available; a dead hold stops them. Plain Aerators (bubble columns) oxygenate unpowered. See Fish.
Supplements: a dosed pool
Supplements are phosphorus, potassium, and iron (P/K/Fe). Fish waste is nitrogen-rich but poor in P/K/Fe; fruiting and flowering crops need P/K/Fe dosed in, leafy crops do not.
Supplements live in a persisted dosed pool: a single "pool units" number, topped up by hand and drawn down by fruiting crops. The pool survives restarts and never touches inventory.
How to dose
At the Aquaponics Console (CARTOGRAPHY_TABLE):
- Hold any
aquaponics.supplement.*item. - Right-click the Console.
- One supplement item is consumed; the pool goes up 30 units per item.
Buy supplements from the shop, or fabricate them from mined feedstocks: phosphate and potash come from rocky-planet deposits (see Planets); Iron Chelate is fabricated from asteroid-mined Raw Silica plus refined iron. A Fabricator turns each into its matching supplement.
The Console confirms with "Dosed supplements (pool ~N units). Fruiting crops draw from this; leafy crops don't need it." There is no automated feed: supplements cannot be piped from a hold.
Which crops need it
Per-minute supplement demand by crop:
| Crop | Type | Supplement demand / min | Needs dosing? |
|---|---|---|---|
| Lettuce | leafy | 0.0 | No |
| Wheat | fruiting | 0.05 | Yes |
| Tomato | fruiting | 0.15 | Yes |
| (any other crop) | (other) | 0.02 | Yes |
Leafy crops demand 0.0; an empty pool never penalises them. Fruiting crops stall completely on an empty pool; their supplement factor drops to zero. See Crops for wilting and the other limiting factors.
How the pool drains (pooled satisfaction)
The pool is shared across all fruiting crops:
- Each minute, the system totals the demand of every fruiting crop.
- It draws that much from the pool, or as much as the pool can cover.
- The fraction of demand covered becomes the satisfaction, applied to every fruiting crop equally.
If the pool covers half the total fruiting demand, every fruiting crop grows at half its supplement-limited rate. Pooling never touches leafy crops.
One supplement item adds 30 pool units. A single tomato (0.15/min) draws 30 units down over ~200 minutes of online growth; a bed drains it proportionally faster. The Console reports the pool as "minutes of buffer left versus current fruiting demand" and names supplements as the limiting factor when they're the constraint.
Scaling up
| Front | Cost |
|---|---|
| Power throughput | More beds → more lamps; burn scales linearly (lamp output × 0.1 cells/min) |
| Supplement labour | Fruiting crops (tomato 0.15/min, wheat 0.05/min) drain the pool; dose by hand, +30 units per item, no automation |
| Chemistry risk | Density pushes more fish into the tank; over-stocking tips the lethal ammonia/oxygen cascade (see The Nitrogen Cycle) |
A 2-lamp, lettuce-only build burns ~1 Drive Cell / 5 min and needs zero supplements.
At a glance
| Question | Answer |
|---|---|
| What do lamps burn? | Drive Cells (ammo.drive_cell) from the GENERAL hold, the only hold draw |
| How fast? | ~0.1 cell per lamp-unit per minute; a 2-lamp farm ≈ 1 cell / 5 min |
| What happens on an empty hold? | Buffer drains → lights dim → all crops slow; powered pumps stop aerating |
| Do fish-only farms burn power? | No: no lamps, no draw |
| Where do supplements live? | A dosed pool on the farm, never a cargo hold |
| How do I dose? | Right-click the Console holding a supplement item (+30 pool units each) |
| Which crops need supplements? | Fruiting (wheat, tomato) stall when empty; leafy (lettuce) never need any |
| Is dosing automated? | No: no hold feed; dose by hand at the Console |