Double stacking sponge filter

[Biago]

Hi All,

Looking for some advice. I switched my tank to a sponge filter from a canister. It is a soil with sand cap; planted 75 gallon. Sofar I love the quieter noise, and far easier operation. I have great flow with the easy flow adaptor 1/2 showing at the surface. 

Tank parameters: stable at 20-25 Nitrates, PH 6.8-7, mid range for GH and KH. No Ammonium or chlorine. 

My challenge has been the sponge only seems to be using the top 5-10% of the filter. I connected my airline to the handy port. My water doesn’t seem to clear up from the sponge. I put in a small oase skimmer and hair tied a piece of white sponge to it to test- this seems to clean the water overnight (and gets very dirty). So my thought is that the air isn’t creating enough draw to use both sponges. 

I am wondering if I should place the air line with  air stone and place it further down in the lower sponge.

Anyone else have experience with this?

Pictures of the tank(sorry low res, hi res was giving me problems), and a closeup of the top of the filter and my test skimmer setup(freshly cleaned)

Thank you in advance!

Edited March 27 by Biago

[AllFishNoBrakes]

A sponge vs. a canister, the sponge has way less mechanical filtration abilities. However, over time, the pores of the sponge become smaller and smaller as they fill with detritus, which means it will collect smaller and smaller particles and polish your water more. 
 

I cleaned a sponge today that hadn’t been cleaned in months. It was almost hard to the touch it has collected so much detritus. I was shocked, but it made sense.  
 

Can you stuff that internal filter with Poly Fill? That could become your “water polisher” and the sponges can do what sponges do. 

Edited March 27 by AllFishNoBrakes

[Biago]

This is point I didn’t think about! I had actually cleaned it thinking it was clogged- I would have reset its progress there  🙂

Yes, it’s a small area, but certainly can plug it will some poly- I’ll do that! Thank you so much for your wisdom 🙂

[Tony s]

On 3/26/2024 at 8:44 PM, Biago said:

Sofar I love the quieter noise

My thoughts, your canister is louder than your sponge. I’m thinking your canister has issues. I almost never hear mine. 
 

agree with @AllFishNoBrakes  sponges are not good at polishing the water, they work best for biological filtration. And cleaning, bags or whatever usually doesn’t work good, and a lot of junk ends up back in the water. I think I’d figure out why you’re canister is so load

[Biago]

It might be more appropriate to say “different”. But decibel wise I would say less.  With the co-op air pump and the easy flow, it’s a nice water trickle sound and that’s it. 

Another consideration was power loss- a lot easier for me to backup the sponge filter (the air pump has battery backup and can run off USB external power if needed).

To me- the canister felt like a pain to clean. It felt like a process to open and clean and I always seemed to make a mess.

For whatever reason mentally I was always worried about the canister turning off or getting air in it or leaking- the sponge has given me more peace of mind-  which allows me to enjoy my tank even more 🙂 

[TOtrees]

On 3/27/2024 at 1:34 AM, Tony s said:

sponges are not good at polishing the water

Coop sponges are not good at polishing water, because of how open/coarse they are. The tradeoff is they require cleaning way less. But there are other sponges that have a much higher ppi sponge that do a decent job at polishing. And require rinsing more often. 

I'll also second that sponges are, to some extent, self adjusting. In your sponge filter pics @Biago yes we can see mulm at the top. This is because enough water enters the center chamber through the sponges just at the top, that everything below that doesn't need to flow through to work. All that sponge lower down is viable surface area, but it's not receiving any/much flow. But, as the pores up top get clogged with mulm, the amount of water passing through there will diminish, and water will have to pass through lower down. And so on. Unless you rinse it, which resets the process. 

I do think you would have no loss of filtration capacity/ability by going down to 1 sponge only, based on what I'm seeing here. 

I also think you might get better uplift/flow if you do as someone above suggested and put an airstone inside the sponge. Though how to do that with the easy flow I'm not sure. The few coop sponges I run (without easy flow) have the Lee's Discard-A-Stone inside, because they are narrower and produce a finer bubble than most ceramic stones. 

[Tony s]

On 3/27/2024 at 7:56 AM, Biago said:

Another consideration was power loss- a lot easier for me to backup the sponge filter (the air pump has battery backup and can run off USB external power if needed).

I have an air stone on back up for that. So I can understand. As for cleaning, my 8 yr old daughter likes to help and play in the gunk. We do make a bit of a mess, but nbd. This is actually house work she likes 🤣 I run an fx2 in cabinet so never hear anything from it at all