Fish Guard vs Shrimp Guard: Which Intake Guard Fits Your Tank
The main difference is slot width. A shrimp guard uses a 1.5mm slot, narrow enough to stop shrimp and fry. A fish guard uses a wider 4.0mm slot, built for tanks where shrimp size is not the concern, just keeping fish and larger debris off the intake.
This guide covers which guard fits which situation, and points you to our deeper shrimp guard guides for sizing and setup, so we do not repeat that content here.
What is the difference between a fish guard and a shrimp guard?
Both are slotted cages that cover a filter intake. The cage design is the same idea either way. The difference is the slot width cut into the wall.
| Guard | Slot width | Built for |
|---|---|---|
| Shrimp guard | 1.5mm | Stopping shrimp, shrimplets, and fry from reaching the intake |
| Fish guard | 4.0mm | General intake protection where shrimp size is not the concern |
Slot widths are our own products' published specs. Neither guard is a guarantee. No guard is a substitute for watching your tank.
Do I need a shrimp guard or a fish guard?
If you keep shrimp, especially breeding shrimp with shrimplets in the tank, the narrower 1.5mm shrimp guard slot is built for that size of animal. A wider fish guard slot is not narrow enough to reliably stop something as small as a shrimplet.
If you do not keep shrimp, or your shrimp are grown adults you are not actively breeding, a fish guard's wider slot still keeps fish and larger debris off the intake, with less restriction on flow than the narrower shrimp guard slot.
Can I use a fish guard in a shrimp tank?
Not if fry or shrimplets are present. The 4.0mm fish guard slot is wide enough that a small shrimplet can pass through it. Use the 1.5mm shrimp guard in any tank where shrimp are actively breeding.
If your shrimp are all grown adults and you are not breeding, some keepers use the wider fish guard slot without issue, but the shrimp guard remains the safer, purpose built choice.
What size intake does each guard fit?
Both guards are sized to the same set of hose barbs, so you match the guard to your hose size the same way either way.
| Intake hose size | Shrimp guard | Fish guard |
|---|---|---|
| 9/12mm | Available | Available |
| 12/16mm | Available | Available |
| 16/22mm | Available | Available |
| 25/34mm | Available | Available |
Hose sizes come from fitment-data.ts, sourced from Eheim and JBL's own spec pages. Both guards also come in a SunSun HW-304 size and a Fluval Large/XL size, not shown in this table since those two barbs are not yet a fitment-data.ts row.
Frequently asked questions
What is the difference between a fish guard and a shrimp guard?+
Slot width. A shrimp guard uses a 1.5mm slot to stop shrimp and fry. A fish guard uses a wider 4.0mm slot for general intake protection where shrimp size is not the concern.
Will a fish guard stop shrimp from getting into my filter?+
Not reliably. The 4.0mm slot is wide enough that a small shrimplet can pass through. Use the 1.5mm shrimp guard if fry or shrimplets are in the tank.
Do fish guards and shrimp guards fit the same hose sizes?+
Yes. Both are made in the same set of hose barb sizes, so you match either guard to your hose size the same way.
Does either guard guarantee my animals will be safe?+
No. Both lower the risk by covering the intake, but flow, slot size, and the size of your animals all play a part. Keep watching your tank after you install either one.
A note on safety
We print every part in PETG. It is the material aquarium keepers have used submerged for years. We cannot promise how any part performs in your tank. You know your tank and your animals best, so the call is always yours. Rinse each part in clean water before you add it to your tank.
Shop the guard that fits your tank
Shrimp guards cut a 1.5mm slot for shrimp and fry. Fish guards cut a wider 4.0mm slot for general intake protection. Made in the USA. Printed in the USA when you order.
Need the narrower slot? Shop shrimp guards →
