Using a smaller model impeller on Aquaclear

I currently use 2 Aquaclear 50s on 2 20 gallon longs and an Aquaclear 30 on a 10 gallon.

I’ve read articles where, since the Aquaclear models 20-70 all use the same motor and just change the impellers and media trays, people have toyed with using alternate impellers to increase or decrease flow in their filter. Most of the threads I’ve read have said it tends to work within one size, ie the 50 impeller will work on the 70 or the 30.

I’m going to need to pick up another filter for another 20 gallon long and I have an extra 50 impeller that’s currently unused. I was toying with the idea of picking up a 70 instead of another 50 and switching out the impellers so I’d have the larger media basket to use.

Has anyone done this? Did it work? Did it cause problems over time?

I’m very curious about the possibility.

 

Just in case anyone else comes along and tries this: yes, it works, but it’s ultimately not worth the hassle. Just use the filter out of the box.

 

Was the flow of the AC70 using the 50's impeller too slow ?

 

No, it works just fine, but an AC70 with an AC50 impeller is prone to noisy bouts, has bizarre water output and, due to the size of AC70’s intake tube, really isn’t that much of a reduction in current or surface disruption (for fish like Gourami).

In most cases a stock AC50 or AC70 is a better choice.

That said, you can use an AC70 with an AC50 impeller on something like a 20 long and, unless your goal is to have a nanofish Sharknado, a regular AC70 in that setup isn’t a good fit.

 

Really depends on what media your putting in the basket part. The impellers are designed for the flow rate through the media in that basket.

I see people doing this with refugium mods in the salt world all the time - to specifically reduce the flow rate... it really depends I guess on what your really trying to achieve by going bigger basket though? The media in a AC50 (even the AC30) should be more than enough to sustain a 20 long.

 

...it really depends I guess on what your really trying to achieve by going bigger basket though? The media in a AC50 (even the AC30) should be more than enough to sustain a 20 long.

Exactly. I have Media Baskets in my AC70 that make it easier to change out media, so I did this for awhile until I got my 29 gallon tanks up and running, but honestly, aside from the ability to hide a heater in the filter, there aren’t really any reasons to use an AC70 on something like a 20 long.

Depending on your stocking, even an AC50 could be overkill.

 

Exactly. I have Media Baskets in my AC70 that make it easier to change out media, so I did this for awhile until I got my 29 gallon tanks up and running, but honestly, aside from the ability to hide a heater in the filter, there aren’t really any reasons to use an AC70 on something like a 20 long.

Depending on your stocking, even an AC50 could be overkill.

I've not looked at compact heaters, but that is a great idea to put heater in one. Same we do on sumps.

Not sure what happened probably sleep deprived when I posted lol. I read your first post but didn't realize you were following up on it. Lol

 

This is the media basket I use in the AC70s. There’s room for one or more compact heaters along with a floss pad (or 2 or 3) in the vertical compartment.

After no small amount of searching, I found that two of these heaters fit nicely in the vertical compartment along with a filter floss pad. They can usually be found for around $10-$15 each.

You can also fit one of these in there, if you want something adjustable at a comparable wattage. This is the smallest 100w I found, but the cord makes it hard to close the lid. I’m not sure if it’s possible to fit a 2nd.

If you step down to 50w heaters, your options open up. This is a good inexpensive option. You can also spend more for even smaller options, some of which you could fit 4 of in that space, but the cheapest option I’ve found in that vein added up to about $150...for heaters.

For the record, you can do this without a specialized basket, but it gets increasingly less safe to do so when things aren’t split up a bit. I’ve read a number of stories of people melting filters playing hide-the-heater.

I managed to fit a 100w Aqueon preset heater, 125ml of Seachem Matrix, 15 Marineland Bioballs, a filter floss pad, and a 100ml in-bag pack of Purigen in an AC50 using the default tray; but I took a look at it, decided I didn’t want to burn down my home, and removed the heater.

It’s also worth noting that a basket like that, plus the HOB filter, before media, heaters, etc. is about the same cost as an entry-level canister filter. This might be a better option, depending on your needs.

Personally, I like the HOB with basket because I can flip a switch on a power strip to turn off the heaters, flip another Switch 30 minutes later to turn off the filters, open the lid, change out the filter pads, clean any coarse sponges, and change out chemical media without having to pull out trays or anything. It takes a heck of a lot longer to clean out my AC 50s with the stock trays.

 

Is there a way to tell what impeller is for what filter housing? I got two impellers mixed up and I think I have the wrong one in my AC50.
This was a good subject because I have had questions about AC motors and impellers for a while now.
Same motor for both my AC 50 and AC70. Supposedly only difference is the impeller. I have both and looked them over very well and see absolutely no difference between them.
Makes zero sense as the filter has a GPH rating.
If everything is the same (motor and impeller) how could there be sizes at all? I mean the only thing that changes is the housing and the intake tube. They both should move the same amount of water.
So how can an AC70 move more water than an AC50 if both the impeller and motor are the same?
Also if there is a difference, how can I mark the impeller to identify it?

 

Is there a way to tell what impeller is for what filter housing? I got two impellers mixed up and I think I have the wrong one in my AC50.
This was a good subject because I have had questions about AC motors and impellers for a while now.
Same motor for both my AC 50 and AC70. Supposedly only difference is the impeller. I have both and looked them over very well and see absolutely no difference between them.
Makes zero sense as the filter has a GPH rating.
If everything is the same (motor and impeller) how could there be sizes at all? I mean the only thing that changes is the housing and the intake tube. They both should move the same amount of water.
So how can an AC70 move more water than an AC50 if both the impeller and motor are the same?
Also if there is a difference, how can I mark the impeller to identify it?

I believe each impeller is different on the white plastic part that moves the water some are bigger or more prongs (I'm not sure exactly what they are called). The impeller is the difference between the sizes, the motor is the same. It's the impeller that increases and decreases the water flow.

 

I believe each impeller is different on the white plastic part that moves the water some are bigger or more prongs (I'm not sure exactly what they are called). The impeller is the difference between the sizes, the motor is the same. It's the impeller that increases and decreases the water flow.

This is mostly correct. The impeller on the AC30 and AC50 has 4 blades at the top, with the AC50 impeller being slightly taller. The AC70 has 6 blades.

The AC70 also has a significantly larger intake tube which amounts to most of the jump in water output between it and the AC50. This is why changing the impeller on an AC70 doesn’t pay off as well as might be expected.

 

This is mostly correct. The impeller on the AC30 and AC50 has 4 blades at the top, with the AC50 impeller being slightly taller. The AC70 has 6 blades.

The AC70 also has a significantly larger intake tube which amounts to most of the jump in water output between it and the AC50. This is why changing the impeller on an AC70 doesn’t pay off as well as might be expected.

I will look again today, but the impellers look identical on my AC50 and AC70.

 

Here’s a picture of the motor off an AC70 with an AC70 impeller:




You can see it has six white blades at the top. I didn’t have a readily available AC50 impeller (they’re all in-use), but it would only have 4.

Edit: It figures that I’d see one in a parts bucket once I posted that.

This is what the AC30/AC50 impellers look like:



As you can see, these only have 4 blades. The difference between the 30 and 50 is more subtle as the white portion of the AC50 is a little taller.

 

Here’s a picture of the motor off an AC70 with an AC70 impeller:

View attachment 764844

You can see it has six white blades at the top. I didn’t have a readily available AC50 impeller (they’re all in-use), but it would only have 4.

Edit: It figures that I’d see one in a parts bucket once I posted that.

This is what the AC30/AC50 impellers look like:

View attachment 764849
As you can see, these only have 4 blades. The difference between the 30 and 50 is more subtle as the white portion of the AC50 is a little taller.

Thank You. I do not have either in front of me. But there was no difference in impeller blades between my 50 and 70.
In fact, I know none of the impellers I have are 4 blade. They all have 6 blades. I only own the 50 and 70.
Maybe they got mixed up at the manufacturer or the seller? The package can be opened without hurting the product so who knows what may have happened.

Also I vaguely remember talking to a Fluval rep about this and they told me the difference was the blade pitch. Now this makes perfect sense. Blade count also makes perfect sense.
I am going to double check all the impellers I have and see.
I really appreciate your help on this. You may have found the issue.
Also it seems to not matter at all, even if they were wrong out of the box. They both work and there is no difference in performance that I can see.

 

Thank You. I do not have either in front of me. But there was no difference in impeller blades between my 50 and 70.
In fact, I know none of the impellers I have are 4 blade. They all have 6 blades. I only own the 50 and 70.
Maybe they got mixed up at the manufacturer or the seller? The package can be opened without hurting the product so who knows what may have happened.

Also I vaguely remember talking to a Fluval rep about this and they told me the difference was the blade pitch. Now this makes perfect sense. Blade count also makes perfect sense.
I am going to double check all the impellers I have and see.
I really appreciate your help on this. You may have found the issue.
Also it seems to not matter at all, even if they were wrong out of the box. They both work and there is no difference in performance that I can see.

The major difference between the 50 and 70, aside from the baskets, is the size of the intake tube. While the 6-bladed impeller will draw more water, it’ll get bottlenecked by the intake tube.

This may cause extra wear on the motor and shaft over time, but I doubt it’d be significant.

I’ve read that people sometimes run the AC20 impeller on the AC70 for refugium use, so I don’t think stepping up one impeller is going to do any major damage, but I definitely wouldn’t do it by more than one step!

 

The major difference between the 50 and 70, aside from the baskets, is the size of the intake tube. While the 6-bladed impeller will draw more water, it’ll get bottlenecked by the intake tube.

This may cause extra wear on the motor and shaft over time, but I doubt it’d be significant.

I’ve read that people sometimes run the AC20 impeller on the AC70 for refugium use, so I don’t think stepping up one impeller is going to do any major damage, but I definitely wouldn’t do it by more than one step!

Thanks again.
I had to turn off my AC50 as it was making a racket. So its a good time to see whats in there. I hate to pull the 70, but seems like the only thing to do.
But I will look at both. I am fairly certain they will be identical? So 4 blades for the 50 and 6 blades for the 70?

I also have to clean the glass. Two weeks since I cleaned it. Terrible. I wonder if a UV sterilizer would help? Seems its geared to suspended algae in the water?

 

Honestly, elbow grease is the best answer there.

Scrape the glass with a blade (the ones they sell at places like Petco with a long handle are easiest); scrub it with a brush, sponge, or mag cleaner; then do a partial water change, sucking up whatever you can.

You’ll see a vast improvement immediately and a continued improvement over time.

 

Honestly, elbow grease is the best answer there.

Scrape the glass with a blade (the ones they sell at places like Petco with a long handle are easiest); scrub it with a brush, sponge, or mag cleaner; then do a partial water change, sucking up whatever you can.

You’ll see a vast improvement immediately and a continued improvement over time.

I know how to get it off, its the emergence of the algae after only two weeks that bothers me. Seems faster than usual?
I have the long handled razor type scrapper you mention along with a sponge with a soft side and a scrubbing side.
I no longer use the scrapper unless its just a tiny bit to remove. Using a scrapper allows the algae to remain in the tank to grow. I now use the sponge and squeeze it out after each pass. I try to get the algae I remove into the bucket instead of the tank.
To get the algae out of the tank.
How would a scapper help with algae control? It does get it off the glass, but does not do anything for retarding growth.
Thats why I am thinking about a UV sterilizer. I think they are designed for suspended algae in the water? I hope someone chimes in on this.

I am only using the lights for 6 hours a day and the tank is not getting much ambient light either. There is no direct sunlight and the room is kind of dark as well.

 

I had a similar explosion recently after over-culling the duckweed in a tank.

A meticulous glass scrape and sponge scrub was the first step, followed by hand-pulling the floating and loose bits. The fish have been working on the rest.

I’ve been leaving the duckweed alone to grow for now, as well as transplanting some of what I culled from the other tanks. This has helped reduce the algae’s ability to grow back. The other plants have started to pick up some of the slack, too.

Algae blooms are usually due to an upset in the balance of the biome in the tank. In my case, I severely cut back the duckweed population, which gave the algae room to gain a foothold and propagate. This then hurt some of the slower-growing plants like my swords and tiger lotus. With them getting weaker, the algae was then able to further dominate the ecosystem.

While UV cleaners will provide a quick solution, the dirty secret is that, if you don’t solve the underlying problem, the algae will just keep returning, requiring you to repeatedly use the UV treatment. If you then go on to rely on additional chemical treatments you end up in a loop of treating symptoms instead of solving the underlying problem.

I did not mean to come across as rude or condescending in the prior post. I just think it’s instinctual for us to look for external solutions and throw money at them. The truth is, most of the time, we already have what we need to solve the problem and I’d hate to see anyone spend money on a solution to a problem that can be solved with tools they already have available.

That said, I don’t know the extent of your algae issue, nor do I know all that you’ve tried so far. I do know how exasperating algae blooms can be and how maddening it is to watch a tank go from a beautiful work of lovingly-planted and painstakingly aquascaped art to gross pea soup seemingly overnight.

I just hate seeing anyone fall down the hardware and “algae eater” rabbit hole if there are still simpler solutions to their problem.

 

I had a similar explosion recently after over-culling the duckweed in a tank.

A meticulous glass scrape and sponge scrub was the first step, followed by hand-pulling the floating and loose bits. The fish have been working on the rest.

I’ve been leaving the duckweed alone to grow for now, as well as transplanting some of what I culled from the other tanks. This has helped reduce the algae’s ability to grow back. The other plants have started to pick up some of the slack, too.

Algae blooms are usually due to an upset in the balance of the biome in the tank. In my case, I severely cut back the duckweed population, which gave the algae room to gain a foothold and propagate. This then hurt some of the slower-growing plants like my swords and tiger lotus. With them getting weaker, the algae was then able to further dominate the ecosystem.

While UV cleaners will provide a quick solution, the dirty secret is that, if you don’t solve the underlying problem, the algae will just keep returning, requiring you to repeatedly use the UV treatment. If you then go on to rely on additional chemical treatments you end up in a loop of treating symptoms instead of solving the underlying problem.

I did not mean to come across as rude or condescending in the prior post. I just think it’s instinctual for us to look for external solutions and throw money at them. The truth is, most of the time, we already have what we need to solve the problem and I’d hate to see anyone spend money on a solution to a problem that can be solved with tools they already have available.

That said, I don’t know the extent of your algae issue, nor do I know all that you’ve tried so far. I do know how exasperating algae blooms can be and how maddening it is to watch a tank go from a beautiful work of lovingly-planted and painstakingly aquascaped art to gross pea soup seemingly overnight.

I just hate seeing anyone fall down the hardware and “algae eater” rabbit hole if there are still simpler solutions to their problem.

No you are fine!
My algae issue is the glass. No pea soup. No algae bloom. Regular cleanings remove it until it comes back. Thats the issue. Glass getting algae quickly.
I agree on the hardware point. I just was hoping to find something that might keep the glass cleaning to a minimum.
Thanks