Can Anyone Explain Why Water Looks Clearer When AC Filter is on Lower Flow Rate?

[Kaskade1309]

On my 60 gallon fancy goldfish tank -- currently populated with two fish, a common orange fantail and calico fantail -- I'm running an Aqueon QuietFlow LED Pro 75 HOB and AquaClear 110 HOB, and, as everyone knows, the AquaClear has an adjustable flow rate knob (which the Aqueon does not). I have found -- contrary to everything I've been told by other AC owners based on their experience using these -- that my water looks more polished and clear when I leave the flow set to the lower side of the intake control (the "-" side). I know Hagen/Fluval has all that marketing hoopla about how the lower flow rate enables more water to be filtered over and over again, but from what just about every hobbyist has told me in this arena, the filter should always be set to max flow.

I find there are more bits of debris that are, apparently, "missed" by the media in the 110 with the flow all the way up...as it stands, the filter is loaded with the stock Fluval foam block on the bottom, a layer of floss on top of that, two 100ml bags of Purigen on top of the floss and two small sacks of the Fluval BioMax as the final layer.

Does anyone else experience better water quality with their filter flow lowered down?

[Slaphppy7]

Welcome to the AC.

I've never noticed a difference with different flow settings affecting water clarity, personally....and in a cycled tank, the flow rate does not have to be set to max.

I have many of the AquaClear filters, and don't use the sponge that comes with them, just a layer of poly quilt batting that I change out weekly on the bottom, and the rest of the filter filled with ceramic media...I find sponges to be messy and hard to clean.

You can get a large roll of the poly batting at Walmart for around $10, cut the pieces to fit the filter...cheap, easy, and the roll lasts a very long time...no more cleaning of sponge filters.

[Kaskade1309]

Welcome to the AC.

I've never noticed a difference with different flow settings affecting water clarity, personally....and in a cycled tank, the flow rate does not have to be set to max.

I have many of the AquaClear filters, and don't use the sponge that comes with them, just a layer of poly quilt batting that I change out weekly on the bottom, and the rest of the filter filled with ceramic media...I find sponges to be messy and hard to clean.

You can get a large roll of the poly batting at Walmart for around $10, cut the pieces to fit the filter...cheap, easy, and the roll lasts a very long time...no more cleaning of sponge filters.

Thanks for the reply, Slap, and for the welcome.

Can you explain a bit better what you meant by a cycled tank not needing to be on max flow? I didn't know that cycling made a difference here; the tank was recently cycled back up after being dormant for some time, and we used Stability by Seachem to kickstart the process, but I didn't know the flow rate of a filter had anything to do with this...

As for the sponge/foam block...I don't have an issue with mine in the 110. I just dunk and rinse it out from time to time in removed tank water.

[Slaphppy7]

You are very welcome.

How long has the tank been set up, with or without fish?

[Kaskade1309]

Your are very welcome.

How long has the tank been set up, with or without fish?

Tank has been up for about two months. Started with an empty tank and a first course of Stability. Added two starter fancy goldfish before the first round of Stability was up, per Seachem's suggestion (they claim the product needs fish waste to properly begin colonizing in the system), which are still with us now and doing VERY well, growing, eating, playing and being overall very happy. Seachem then recommended I add another week's dose of Stability when my water parameters weren't really changing based on the API test results, and then things seemed to stabilize. Water got super clear and remains that way, and I'm running Purigen (200ml) in the AquaClear 110.

[Slaphppy7]

Get an API Freshwater liquid test kit, you may be in the midst of a fish-in cycle...run tests for ammonia, nitrIte, and nitrAte...you really don't need the Stability or anything else besides the test kit and a good water conditioner, Seachem Prime is the best out there, IMO

[toddnbecka]

I found that using 2 or 3 sponge blocks in aquaclear filters is the best way to use them. The carbon isn't particularly useful unless you're removing medication/s from the tank, and the extra sponge catches more debris. Just rinse them in the sink when the flow rate slows down, and don't worry about killing off the bacteria with tap water. The beneficial bugs don't die that quickly or easily, lol.

[SueD]

I found that using 2 or 3 sponge blocks in aquaclear filters is the best way to use them. The carbon isn't particularly useful unless you're removing medication/s from the tank, and the extra sponge catches more debris. Just rinse them in the sink when the flow rate slows down, and don't worry about killing off the bacteria with tap water. The beneficial bugs don't die that quickly or easily, lol.

"Just rinse them in the sink" - lol, this is considered heresy in many places. I've been rinsing my sponges for years at the kitchen sink, in tap water. Best way to get them clean and have never had any ill effects. I use sponges, prefilter sponges and ceramic media in all of my hob filters and clean all of them this way.

[Slaphppy7]

You clean ceramic media in chlorinated tap water?

[SueD]

You clean ceramic media in chlorinated tap water?

Yep. They just get rinsed while in the bag to get the "gunk" out. The sponges get squeezed several times, depending on how long I go between cleanings.