Aquarium Filters · owner-verdict comparison

AquaClear 70 Power Filter vs Fluval FX6: what real owners say

Real owners lean toward the Fluval FX6: 77% of 349 owners recommend it, vs 45% of 22 for the AquaClear 70 Power Filter.

Verdicts aggregated from Reddit, enthusiast forums, and YouTube owner comments — affiliate reviews excluded. Sample sizes differ; judge accordingly. How we score

AquaClear 70 Power Filter

45%of 22 owners recommend

45% recommend · 41% neutral · 14% don't

Owners praise

Widely regarded as the best hang-on-back filter on the market, with several owners switching from brands like Aqueon and saying they'll never go back
Extremely reliable and long-lasting, with some units still running decades after purchase (one owner still runs an AquaClear 70 from 1990)

Owners complain about

Can be finicky to restart after a power outage or once the impeller gets dirty, sometimes needing repriming or grinding/failing to cycle water at all
Outflow is quite strong out of the box and often needs configuring to tame, with a few owners removing it from planted tanks because it was blasting their plants

Full owner report →

Fluval FX6

77%of 349 owners recommend

77% recommend · 8% neutral · 15% don't

Owners praise

Keeps water crystal clear
Huge media capacity and powerful flow for big tanks
Long intervals between cleanings

Owners complain about

Expensive, especially next to SunSun
Large, needs a tall cabinet or floor clearance
Finicky to prime and gurgles when not below water level

Full owner report →

Which should you buy?

Get the AquaClear 70 Power Filter if

✓Owners who want a customizable media chamber, similar to a canister filter but cheaper
✓Planted or reef HOB setups running refugium media like chaeto, floss, and purigen
✓Aquarists prioritizing reliable long-term mechanical and biological filtration over years of use
✓Tanks needing strong flow and surface agitation, like sponge- or gravel-based freshwater setups

Skip it if

Owners intolerant of occasional repriming or restarting after power interruptions
Delicate planted tanks where strong outflow can damage or uproot plants

Get the Fluval FX6 if

✓Large-tank owners from 75 gallons up to 400
✓Turtle and messy-fish keepers needing heavy filtration
✓People wanting months between filter cleanings
✓Owners prioritizing quiet operation and replaceable parts

Skip it if

Budget shoppers who find SunSun good enough
Small tanks where the flow overwhelms fish

What AquaClear 70 Power Filter owners say

“I still have an old AquaClear70 from 1990 that I still run”
— TheBlackStache on Reddit

“it works great but the flow is pretty strong”
— DFlyLoveHeart42 on Reddit

“Ran it completely empty, i.e. no filter media or sponge, and it still shut off randomly.”
— ElizzaBum on Reddit

What Fluval FX6 owners say

“I use fx6 on my bowl betta tank and his happy.”
— @linslins4860 on YouTube

“I have an fx6 running on my tank and it’s the best I have ever used.”
— @MrBertie1982 on YouTube

“If it wasn’t for all those screws just to open it…”
— @deShadua on YouTube

AquaClear 70 Power Filter vs Fluval FX6: frequently asked questions

Is the AquaClear 70 Power Filter or the Fluval FX6 better?

Real owners lean toward the Fluval FX6: 77% of 349 owners recommend it, vs 45% of 22 for the AquaClear 70 Power Filter.

Who should get the AquaClear 70 Power Filter?

Owners point the AquaClear 70 Power Filter at owners who want a customizable media chamber, similar to a canister filter but cheaper, and planted or reef HOB setups running refugium media like chaeto, floss, and purigen.

Who should get the Fluval FX6?

Owners point the Fluval FX6 at large-tank owners from 75 gallons up to 400, and turtle and messy-fish keepers needing heavy filtration.

What do owners complain about?

The most-cited downside of the AquaClear 70 Power Filter is can be finicky to restart after a power outage or once the impeller gets dirty, sometimes needing repriming or grinding/failing to cycle water at all. For the Fluval FX6, it's expensive, especially next to SunSun.