Sorry to hear about your lost of job.
Your finance wellbeing is more important than your hobby and fish keeping is not cheap in your country.
By the way, did you check the Fluval C4 setup to ensure that it's being properly installed?
Usually, the noise comes from the intake tube or impeller that is not properly placed/connected to the filter chamber.
Also, you may need to clean the impeller after a while.
I agree with you. When you have too much work(higher maintainence) and stress, you will lose your interest with your hobby.
I know of someone who started to keep fish as a hobby but he ended up losing his interest after he worked for a fish store.
In the fish store, it's a tedious and labour intensive job as he had to do managed many fish tanks.
It's no longer fun when you have too much work to do.
And I fully agree that smaller tanks with fewer & smaller fish are more enjoyable.
I have some suggestions for you:
1)5 gallons tank : with a single Betta. (as mentioned by someone)
This is the easiest to maintain but you may get bored with just a single fish.
Also, take note that long and big fins Bettas tend to have fins rot which will create problem and stress for you.
Plakat Betta is the best.
Keep a single red Betta that has multicolours or Candy colours. I saw so many beautiful Bettas at our LFS recently.
2) 15 gallons tank: with shrimps + some small fish (eg. Chili Rasboras).
After keeping Bettas for a while, I felt bored to keep Bettas alone without other fish.
And I find that shrimps are more interesting than fish.
So, now I am keeping Fire Red, Super Blue and Yellow shrimps + 10 Chili Rasboras in a 15 gallons tank.
Shrimps behaviors are unique and more interesting than fish.
I can sit in front of my tank watching the shrimps whole day.
Shrimps have low bio-loads and you just need to change probably two buckets of water each week(about 50-60% of water or lower, once a week).
Try to have a simple aquascaping with 1-2 big driftwoods, some rocks plus some easy plants to care plants such as Java moss & Anacharis Elodea.
It will make your tank looks very natural and beautiful.
3) Lastly, a 20 gallons long tank.
With this option, you can have slightly bigger fish with a pair of Apistogramma as you centerpiece.
Probably 1 pair of Apistogramma Cacatuoides + 10 Espei Rasboras (Keep some hardy fish like Rasboras or some smaller Tetras species)
Hello Fellow Fish Keepers,In this video we discuss stocking options for a 20 gallon fish tank. We look at some less common ideas and throw in a few old favor...
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In this video I go over some fun setups for a 20 gallon fish tank to give you some new ideas.✅Get Member Status on Youtube ► http://bit.ly/2MeT9nhOn the Aqua...
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For quieter filter, you can try
Internal filter.
But if you are keeping shrimps, you can try
sponge filters or a small canister filter such as Shiruba XB-303.