Decision essentials
Key points
Read order in flow direction, not physical top-to-bottom.
Fine pads first create rapid restriction.
Target media needs independent removal.
Filtration
Protect downstream stages
A prefilter catches leaves, foam shares particle load, and a polishing layer targets the remainder. Biological surfaces then receive less sludge; carbon or resin encounters water with fewer particles.
Some baskets run in parallel or permit edge bypass. Confirm the manufacturer path and seal gaps without compressing media enough to starve flow.
Filtration
Design for the common service
The dirtiest first stage should also be easiest to reach. If cleaning foam requires emptying every ceramic tray, routine work becomes an unnecessary disturbance.
Photograph the stack and record clean flow. Reassembly and restriction are then easier to diagnose.
From evidence to action
Decision matrix
| Situation | What to do | Why |
|---|---|---|
| Coarse debris | Accessible prefilter first | Protects later stages |
| Floss blocks in days | Add coarse stage or reduce fineness | Load is reaching it too early |
| Target adsorbent | Use a removable bag | Exhausted media must leave |
Check the result
After the adjustment, measure flow under the same conditions and check noise, leaks, waste accumulation and circulation. Record the result; if performance drops again, locate the restriction before changing another part of the system. For “Filter media order: map the water path before stacking trays”, use target media needs independent removal as the final article-specific check.
Evidence
Sources and scope
Sources include institutions, technical studies and manufacturers. Chezur separates established mechanisms from editorial decisions for home aquariums.