Concealed 3 Stage Filtration Function?

I have recently moved my veiltail Betta, Finley, from his 2 gallon room (yes, I fell for that mistake) into a 15 gallon (56 liter actually) cycled Aqua Japan AJ-50 house (planted with sand substrate). I'm fairly new to the hobby and I have some questions regarding the tank's filtration system.

It's a concealed 3 compartment system (very similar to the Fluval Flex) Here's a back view:


There's a fairly huge black filter sponge in compartment No1, the water is supposed to the flow from the top to the bottom through the rings in compartment No2 (I have also added some carbon there) up and into compartment No3 in which I have placed a 200lph pump on the bottom that pumps the water back into the tank through a spray bar.

Now, doing the math I realize that pumping 200lph in a 56l tank is barely enough, if at all, but since it's a betta tank I wanted to keep the flow to the very minimum so little Finley won't be flying around like a plastic bag in a thunderstorm. The flow is definitely working for him the way it's set up at the moment.

However, I worried that maybe the water isn't moving sufficiently through the filtration system. I had a spare pump that came with my 2 gallon tank that pumps an insane 400lph. I have placed that pump on top of the rings into compartment 2 with the outlet pointing into compartment 3 where the second pump pumps back into the aquarium. Theoretically I have now increased the waterflow through the filters without increasing the flow into the tank, correct?

This sounds mighty complicated but I'm trying to work with what I have in a country that offers next to nothing in pet shops.

My parameters are: Nitrites, Ammonia 0, Nitrates around 10, PH around 6.5 but I do feel like the water gets murky pretty quickly (I don't think I overfeed). I currently hoover twice a week with around 15% water changes to keep up with it and have a clear tank)

Now my question is, does my concept make sense or am I totally wasting electricity and what I'm doing is completely pointless? If so, what could I do better?
Also, there is no visible "suction" or waterflow in, looking at the top of the black sponge where water is supposed to enter. Is that normal? Shouldn't water visibly flow through it? Maybe people with a Fluval system will be able to help?

I want the best possible conditions for ickle Finley


Thanks in advance for your advice!!

 

Giving this a bump up for you

 

can you take a picture with a light facing the tank...all I am seeing is white ceramic media

"I have placed that pump on top of the rings into compartment 2 with the outlet pointing into compartment 3 where the second pump pumps back into the aquarium. Theoretically I have now increased the waterflow through the filters without increasing the flow into the tank, correct?"

Well I don't think you have though...it would have increased if you made the holes bigger. The only thing the pump is doing is pushing water at the same speed the aquarium filters it at.....so yeah.....you are wasting electricity

 

can you take a picture with a light facing the tank...all I am seeing is white ceramic media

Unfortunately it's hard to take an actual photo from the back. The tank is pretty heavy and there are not many photos online. But like I said, Fluval Flex has a very similar setup (just turned upside down with the sponge and the ceramic in separate compartments)

This is the fluval:



This is a smaller Aqua Japan (not mine) with the same layout

So I have basically placed a second pump on top of the rings in the middle that help suck the water through the filter media at a higher flowrate.

What do you mean "it would have increased if you made the holes bigger" What holes?

 

Unfortunately it's hard to take an actual photo from the back. The tank is pretty heavy and there are not many photos online. But like I said, Fluval Flex has a very similar setup (just turned upside down with the sponge and the ceramic in separate compartments)

This is the fluval:
View attachment 379870

This is a smaller Aqua Japan (not mine) with the same layout

So I have basically placed a second pump on top of the rings in the middle that help suck the water through the filter media at a higher flowrate.

What do you mean "it would have increased if you made the holes bigger" What holes?

Adding a second pump might be a problem as it would pull too much water into the second chamber and cause it to overflow. If anything, just switch the pump it came with for a bigger one. You won't see water flowing through the sponge filter because nothing is moving. I have a 2.6 gallon fluval spec for my betta and you don't see water movement since I don't have any fluidized media or anything.

 

Adding a second pump might be a problem as it would pull too much water into the second chamber and cause it to overflow. If anything, just switch the pump it came with for a bigger one. You won't see water flowing through the sponge filter because nothing is moving. I have a 2.6 gallon fluval spec for my betta and you don't see water movement since I don't have any fluidized media or anything.

I didn't want to put a bigger pump because I don't want to increase the flowrate going into the tank. There are also tubing availability issues where I live and I'm just glad I was able to make something fit lol
The second pump has been running for a couple of days already. It's not so strong to overflow (good point tho!)

Thank you for enlightening me about the sponge. I was expecting to see any sort of "debris" to be visibly sucked into the sponge and I thought something was wrong.

 

What do you mean "it would have increased if you made the holes bigger" What holes?

I meant weirs....if you made the weirs bigger then water would have flown through faster but you would have needed a bigger pump

 

Are you from Italy? Why don't they have anything there?

 

My plakat betta and previous half moon have no problem with higher flow. If you bounce the flow off the side or make sure that it hits some decor to make other areas of the tank peaceful, your betta will be more than fine

 

Are you from Italy? Why don't they have anything there?

I live in the middle east.
Italy made me laugh. I have lived close to Italy as well and I can see why you would say that

My plakat betta and previous half moon have no problem with higher flow. If you bounce the flow off the side or make sure that it hits some decor to make other areas of the tank peaceful, your betta will be more than fine

I have tried a higher flow (my pump is slightly adjustable) and he started tumbling around in half the tank even tho it's pointing at the plants. I guess I can always add an air pump driven sponge filter if I feel filtration is not sufficient.

I'm not sure if it's my imagination but since I've added the second pump I feel like the water is clearer. It's not harming him so I guess I'll just have it run for a while and keep up with the maintenance as needed to give the tank more time to establish itself