The Planted Tank Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
518 Posts
Discussion Starter · #1 ·
I have a Marina 18g aquarium that came with a Marina S20 filter. I am adding a second filter to it and don't know if I should get a AC 30 or AC 50. This is my first aquarium and it will have shrimp.
 

·
Registered
Joined
·
1,945 Posts
Filtration Question

I have a Marina 18g aquarium that came with a Marina S20 filter. I am adding a second filter to it and don't know if I should get a AC 30 or AC 50. This is my first aquarium and it will have shrimp.
Hello Green...

There's no need to over filter an aquarium if you follow a strict water change routine by removing and replacing half the tank water weekly. If you do this, then any filter you use is simply going to be filtering water that's already pure. Doesn't make sense to have a huge filter for a small tank, if you change the water regularly, does it?

A Hagen AC filter for an 18 G only needs to have a gph, gallon per hour turnover rate 6 times the volume of the tank, so that's 108 gallons. The AC 30 turns over 150 gallons per hour. This filter will more than do the job alone and you save between $10.00 to $20.00 by going with the smaller filter. Money you can use to get those special fish you were looking at.

Just a thought.

B
 

·
Registered
Joined
·
430 Posts
IMO you can't really over filter an aquarium. Filtration is good (with the right media), so is flow. For me it comes down to flow - you don't want to be blowing everything around in too strong a current.

I have 2 AC 50's on a 20 gallon and it works very good. Go for the 50 is my suggestion. Make sure you use a sponge on the intake also.
 

·
Registered
Joined
·
1,294 Posts
go for the larger one you can always mod the filter, yes look at the motor #'s there the same model with different impellers that just have larger "paddles" to push more water i tested this even the tiny ac.mini fit and work in a ac 50. i have a ac 50 on my 5.5g i put back the larger impeller an leave it on low as its a 5.5g but i like the larger overflow that doesnt make a strong current. im pretty sure the whole motor can just be twisted out an replaced but i didnt try it to say 100% but same motor should have the same mount ideally, but then again being logical isnt always used in life.
 

·
Registered
Joined
·
301 Posts
The 50 is not a that much bigger than the 30. I would go with a 50 for sure. I own a 20 and a 50. I've also owned a 150 which is the old name for the 30. Between these 3 sizes, i see no reason to ever buy a 20 or 30. The 50 is bigger but not so big that I wouldn't put it on something as small as a 5 gallon tank. If you were asking about a 50 vs 70, that would be the point where i would say the 70 might be too big for some aplications.
 

·
Super Moderator
Joined
·
16,085 Posts
No.

The OP says their tank will house shrimp. That means parameter stability is absolutely key. Changing half the tank's water won't work for them like it would in a tank filled with only Guppies or other livebearers.

Good filtration is necessary for shrimp.

There's no need to over filter an aquarium if you follow a strict water change routine by removing and replacing half the tank water weekly. If you do this, then any filter you use is simply going to be filtering water that's already pure. Doesn't make sense to have a huge filter for a small tank, if you change the water regularly, does it?
About filters... go with the AC70. It's not much more expensive and as others have mentioned, you get much more flexibility. Since you're keeping shrimp, that will be great if you want to add things like Purigen in the future. Also allows for a heater if it's ever necessary.
 

·
Registered
Joined
·
1,945 Posts
Tank Filtration

Hello again Green...

A thought occured to me. If you can't commit to large, weekly water changes, then a larger filter or even two may at least keep the tank water somewhat cleaner.

Remember though, filters just take in toxic water and return water that's a little less toxic. No filter or media made will take the place of a regular water change routine.

B
 

·
Registered
Joined
·
518 Posts
Discussion Starter · #11 ·
Thank you all for the posts.

No.

The OP says their tank will house shrimp. That means parameter stability is absolutely key. Changing half the tank's water won't work for them like it would in a tank filled with only Guppies or other livebearers.

Good filtration is necessary for shrimp.

About filters... go with the AC70. It's not much more expensive and as others have mentioned, you get much more flexibility. Since you're keeping shrimp, that will be great if you want to add things like Purigen in the future. Also allows for a heater if it's ever necessary.
I thought a AC 70 would have too much flow for the shrimp? Be okay with adding the Marina S20 as well? Will have prefilters on them.

Since I never had a aquarium and shrimp, I thought it would be too much. If AC 70 is not that different than AC 50, I might go with the 70. I like the idea of hiding heater if I decide in the future to add one.

Hello again Green...

A thought occured to me. If you can't commit to large, weekly water changes, then a larger filter or even two may at least keep the tank water somewhat cleaner.

Remember though, filters just take in toxic water and return water that's a little less toxic. No filter or media made will take the place of a regular water change routine.

B
There will be water changes.
 

·
Surrounded by Blyxa
Joined
·
1,543 Posts
An AC70 advertises 100gph min to 300gph max on flow control. Add media and a sponge intake, and you've cut that down significantly. People put AC70's on 3gallon Picotopes, they just dremel down the tab preventing further adjustment downwards of flow. Get the bigger filter. I have an Eheim 2028 on a 17 gallon tank and I find the flow simply adequate when you add filter media to the mix.
 

·
Registered
Joined
·
1,945 Posts
Shrimp and Water Changes

Thank you all for the posts.



I thought a AC 70 would have too much flow for the shrimp? Be okay with adding the Marina S20 as well? Will have prefilters on them.

Since I never had a aquarium and shrimp, I thought it would be too much. If AC 70 is not that different than AC 50, I might go with the 70. I like the idea of hiding heater if I decide in the future to add one.

There will be water changes.
Hello again Green...

I kept shrimp for a couple of years in small tanks, before I got into keeping "Livebearers" and found them to be extremely sensative to even a trace of dissolved nitrogen in the water. It was only by changing out half the water in my tanks weekly with pure, treated tap water that I was able to maintain stable water properties. Now, I no longer need to test the water chemistry in my tanks. I know if I change out half the tank water every week, there's no time for nitrogens to build up in the water before the next large change.

Just a thought.

B
 

·
Super Moderator
Joined
·
16,085 Posts
BBradbury: Changing out half the tank water doesn't cut it with shrimp unless you're EI dosing or there's an emergency. Using tap water can also be deadly, depending upon the species.

GreenBliss: As others have mentioned, you can finely tune the flow by adding lots of filter media, a sponge pre-filter and with the flow control that's part of the intake tube.

If you're really concerned about flow, you can also use an impeller (a $3-$5 part) from an AC50 on the AC70 to slow things down a bit. Doubt that will be necessary, though.

I've got an AC70 on a 5.5gal tank and it's perfect. No modifications other than packing it with filter media.
 

·
Registered
Joined
·
518 Posts
Discussion Starter · #15 ·
TexasCichlid said:
An AC70 advertises 100gph min to 300gph max on flow control. Add media and a sponge intake, and you've cut that down significantly. People put AC70's on 3gallon Picotopes, they just dremel down the tab preventing further adjustment downwards of flow. Get the bigger filter. I have an Eheim 2028 on a 17 gallon tank and I find the flow simply adequate when you add filter media to the mix.
GreenBliss: As others have mentioned, you can finely tune the flow by adding lots of filter media, a sponge pre-filter and with the flow control that's part of the intake tube.

If you're really concerned about flow, you can also use an impeller (a $3-$5 part) from an AC50 on the AC70 to slow things down a bit. Doubt that will be necessary, though.

I've got an AC70 on a 5.5gal tank and it's perfect. No modifications other than packing it with filter media.
AC 70 it is. Thank you somewhatshocked and TexasCichlid.
 
1 - 16 of 16 Posts
Top