01 / GOAL
Choose the reef you actually want.
Forgiving softies, bright LPS, mixed reef, SPS showpiece. Start with the outcome, not the spec sheet, and we'll size the build around what that reef needs.
Premium reef planning · free because we don't sell gear
Plan a reef tank that won't punish you later.
Pick your goal, tank, livestock, and gear. ReefCrafter checks compatibility, sizing, and upgrade risks as you build, then sends you to trusted vendors when you're ready.
My 75 gal Mixed Reef
risk reviewTankRed Sea Reefer 250 · 65 gal displaybaseline set
SkimmerReef Octopus Classic 110 · rated 100gthin margin
Lighting2× Hydra 32HD · covers 60×24 footprintcoverage ok
FlowSicce Syncra 3.5 + 2× MP40 · 38× turnovertarget hit
Avoided mistake · undersized skimmerCHECKED 2s AGO
Rules checked
23before you buy
Gear categories
9tank to RO/DI
Checkout
nonebuy where you want
Planning cost
$0free to use
How it works
A premium planning studio, not another aquarium spreadsheet.
Reef tanks fail when the decisions stop talking to each other. ReefCrafter keeps the whole build in view: the goal, the glass, the animals, the gear, the budget, and the risks hiding between them.
02 / BUILD
Add the tank, livestock, and gear.
Pick a tank, sketch the fish list, then choose lights, flow, heat, filtration, and RO/DI. Every choice updates the requirements downstream.
03 / CHECK
Fix the weak spots before they cost you.
ReefCrafter flags the skimmer at the edge, the heater with no redundancy, the light that misses the footprint, and the fish that outgrows the tank.
The compatibility engine
It catches the stuff that ruins month four.
✓
Skimmer rated for 100 gal
DISPLAY 65G · BIOLOAD MED · OK ✓
!
Single heater on 75 gal tank
REDUNDANCY REQUIRED > 50G · WARN
✓
Total flow @ 38× turnover
MIXED REEF · TARGET 30× · OK ✓
Skimmer capacity, not skimmer marketing.
Gallons alone are not enough. ReefCrafter scales skimmer needs against your reef goal and livestock load, then calls out gear that is technically compatible but practically thin.
// skimmer_min = display_gal × bioload_factor
Heat that holds steady without becoming a risk.
Too little heater and the tank drifts. Too much and a stuck-on failure can cook the system. The engine checks wattage, tank size, and redundancy before the cart ever happens.
// 2.5 ≤ total_watts / display_gal ≤ 5.0
Flow and light matched to the animals.
A softie tank and an SPS tank should not buy the same equipment. ReefCrafter checks turnover, head loss, PAR targets, and coverage against the reef you are actually trying to keep.
// turnover = (return_gph × head_factor + Σ powerhead_gph) / display_gal
Popular checks
Start with the question that is already bothering you.
Each guide gives the direct answer first, shows the math, then points you into the planner when you are ready to check the whole build.
Skimmer
Is my skimmer too small?
Check capacity against tank volume and bioload before the cart happens.
Read the check →
Flow
How much flow do I need?
Size powerheads for soft, mixed, or SPS reef goals without overcounting return flow.
Read the check →
Lighting
Will this light work?
Check PAR target and footprint coverage before buying a fixture.
Read the check →
Starting points
Start from a reef that knows its limits.
Use a vetted template when you want momentum. Open the build, understand the tradeoffs, then adjust the tank, tier, livestock, and gear without losing the safety rails.
Free, not shady
Premium planning. Still free.
ReefCrafter does not sell inventory, mark up gear, or lock you into one store. Vendor links may support the tool, but the recommendation has to make sense for the build first.
No checkout
You buy directly from vendors
Vendor-agnostic
The build decides, not the store
Affiliate transparent
Clearly disclosed, never hidden
Free to plan
No card, no gate, no pressure
Build once, regret less
The expensive part should be the tank, not the lesson.
Start with the reef you want. ReefCrafter will keep the parts honest, show the risks, and help you buy with a cleaner conscience when the build is ready.