75 Gallon Tank Is one 55g canister filter plus sponge filters adequate for a 75g tank?

I have an AquaClear HOB 70 on a 40 gallon tank with 1 comet goldfish in it currently.
I want to buy a canister filter for the new tank, but they’re expensive and I just spent almost $800 on a new tank and stand set, plus a python and all the other stuff I’m going to need. Anyways, I’ve worked out almost every kink except for one — now that my tank is up, I realized I couldn’t put the filter I currently have running (the AC 70) on the back because there’s no space between the tank and the wall. I was just going to run that and another filter I had (Marineland bio wheel filter) at the same time, and then I would get a bigger filter later. But now I realize I can’t do that.
I could put them on the sides of the tank but two HOB filters would look extremely tacky on the sides of my tank. So now I’m left with pretty much one choice and that’s a canister filter. I can’t afford one for a 75 gallon tank though, especially not right now. I noticed the ones that are for 55g tanks are significantly cheaper though. So could I just get a 55 canister filter, and then run that with additional filtration in the actual tank? Like with some sponge filters? I don’t want to buy one though if it would be pointless but I really don’t know so I’m asking for opinions. Thank you to anyone who replies!

 

Based on the fluval 307 yes the 55g filter will run 75g tank

 

That should work. Keep up with your water changes and don't overstock and you should be fine. I have a pennplax 700/1000 and 2 bigger sponge filters on my 75g and it's fine.

Don't forget to cycle your new tank or move over your old filter media when you add fish.

 

That should work. Keep up with your water changes and don't overstock and you should be fine. I have a pennplax 700/1000 and 2 bigger sponge filters on my 75g and it's fine.

Don't forget to cycle your new tank or move over your old filter media when you add fish.

I’ve had my eye on the PennPlax 700 for the past couple of days, but the reviews on Amazon have kept me from buying it so far. I’ve read a lot of reviews that its really loud, which would be really bad because my tank is in my room. I’ve never had a canister filter before but I know that I’m looking forward to not hearing so much water trickling all the time. Sometimes I still wake up in the middle of the night and I will literally think it’s raining outside (lol its not so bad anymore, I’ve gotten used to it but is REALLY noisy which can sometimes be annoying).

I also saw a lot of people leave bad reviews because there’s no quick release on the PennPlax 700 along with an issue with too much water bypassing through it.

Its on sale right now for like $85, which is tempting but man… I just don’t know. I was also looking at a SunSun 304B — they have good and bad reviews too which is so difficult when it comes to decision making.

I also have an extreme fear of buying a canister filter in general, because if it were to ever leak, my bedroom floor would fall through and I cannot have that happen. I am so torn about it — it’s driving me batty.

Based on the fluval 307 yes the 55g filter will run 75g tank

The Fluvals are expensive but from what I’ve read they seem to be sturdy. I was trying to stay around the $100 range for the time being, but then I hear my brother in the back of my head telling me that “you gotta remember, you get what you pay for most of the time!” *sigh*

 

Listen to your brother
I would deal with the tackyness of the two HOBs for a while while saving the money to get the Fluval 406/407. I have the 306 on my 55gl, and wish I would have saved for the 406, just from the filter throughput and the additional filter tray capacity.

 

I've read a lot of reviews on different brands of canisters on Amazon before buying my first one.

I would wager 90% of the complaints fall into 2 categories: either their expectations were not realiatic of the filter's capabilities and/or user error.

Knowing how the particular model of canister works by reading the manual thoroughly and watching some YouTube videos will set you up for a long time of trouble-free operation.

If you get a canister, consider buying a small tube of food grade silicone lube. There are many brands and I happen to use Danco Weatherproof Silicone Lube found at big box home improvement or plumbing stores. The silicone lube is used to coat the rubber orings and gaskets of the filter.

You mentioned the SunSun from Amazon.

The brand "Polar Aurora" on Amazon is a rebranded SunSun. Their 525gph model would be an ideal match for your 75g. Actial flow will be only around 60% of advertised flow rating.

If you get a SunSun or Polar Aurora canister, consider getting the version without the included media.

Use the couple $ in savings and buy a set of foam sponge pads made for the filters from the brand "Aquaneat" on Amazon. They will have sets of coarse/medium/fine foam pads for probably $15 to fill your canister up with.

I use layers of foam sponge pads in all my filters for both my mechanical and biological filtration.

 

My pennplax was noisy for the first week until I finally got all the bubbles out of the canister housing. Now it's below my tank on cabinet with the front door closed but the back is open. I don't hear it with the door closed. The outlet could be noisy if you set it up above the main tank surface. I have the tube with like 20 little outlets attached (not the single waterfall thing) and have the tube an inch or two below the surface which makes it quiet. I've had it for 5 months with no trouble except spending an extra 5 min rocking it back and forth to get any bubbles out of the canister after cleaning it. I've heard great things about fluval but just could not afford it at the time. See if you get 20% off with curbside pickup at most big box pet stores right now.

 

I've read a lot of reviews on different brands of canisters on Amazon before buying my first one.

I would wager 90% of the complaints fall into 2 categories: either their expectations were not realiatic of the filter's capabilities and/or user error.

Knowing how the particular model of canister works by reading the manual thoroughly and watching some YouTube videos will set you up for a long time of trouble-free operation.

If you get a canister, consider buying a small tube of food grade silicone lube. There are many brands and I happen to use Danco Weatherproof Silicone Lube found at big box home improvement or plumbing stores. The silicone lube is used to coat the rubber orings and gaskets of the filter.

You mentioned the SunSun from Amazon.

The brand "Polar Aurora" on Amazon is a rebranded SunSun. Their 525gph model would be an ideal match for your 75g. Actial flow will be only around 60% of advertised flow rating.

If you get a SunSun or Polar Aurora canister, consider getting the version without the included media.

Use the couple $ in savings and buy a set of foam sponge pads made for the filters from the brand "Aquaneat" on Amazon. They will have sets of coarse/medium/fine foam pads for probably $15 to fill your canister up with.

I use layers of foam sponge pads in all my filters for both my mechanical and biological filtration.

I took your advice and got the Polar Aurora filter! I’m going to order the sponges once I figure out what exact size I’ll need because it’s kind of confusing. But is this the sealant you’re talking about? I definitely want some peace of mind and I’m the type of person that is “extra” when I do stuff lol. But I figure it’s better to be safe than sorry.

 

Yep, that's exactly what I use.

A little goes a long way. 1 tube lasts a long time.

A good way to practice setting up the canister is to set uo a 5 gallon bucket of water on a chair and place the canister on the ground.

Run the intske and discharge hoses/pipes up to the bucket of water to simulate the tank. Practice priming the canister and let it run for awhile.

 

Yep, that's exactly what I use.

A little goes a long way. 1 tube lasts a long time.

A good way to practice setting up the canister is to set uo a 5 gallon bucket of water on a chair and place the canister on the ground.

Run the intske and discharge hoses/pipes up to the bucket of water to simulate the tank. Practice priming the canister and let it run for awhile.

I’ve got it on my tank now and it’s extremely quiet. My air pump is WAY louder than the canister filter. I absolutely love how my tank looks with no bulky filter hanging off the back of it. I was indecisive about what kind of media I wanted in it, so I just put some coarse, then medium and then fine sponge in the bottom basket. Then in the second basket I put all lava rock, and the third basket I put more lava rock but I’ll probably switch some of that out and buy some ceramic rings to stick in the top basket.

I did have one problem though, with the intake/output hose fittings that are supposed to fit on the back of the tank, don’t fit on the back of my tank. I improvised and have them on there now, and they’re secure but not as secure as they could be. Not sure what I’m gonna do about it but I’m sure I’ll figure something out and for the price of this canister I really can’t complain.

 

If you can post some pics of the problem, we can probably help figure out something