New to the fishkeeping hobby

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.


Aquarium Advice Newbie
Mar 20, 2023
Hello everyone,

Im new to the fishkeeping hobby, 5 weeks ago i got a Fluval Flex 15 gallon and am now thinking about what fish to keep and looking for some extra info and guidelines.

My initial thought is to keep 10 Galaxy Rasbora, 5 Amano Shrimp and 1-2 Nerite snails.

Would this be overstocking it or not?

My water Parameters and tank info:

PH: around 7.0 ( i add CO2 so it tends to change a little bit )

GH: 8-9

KH: 4-4.5
Temperature: Swings around 23°C ( 73°F) to 24°C ( 75°F), when the lights come on it heats up the water, heater had 0 work besides some cold winter nights we had ( its set to 22°C/ 71.6°F )

My lights run from 12pm to 8pm ( stock light + Fluval Aquasky 2.0 )

CO2 runs from 11am to 7pm

I use RO water that i remineralize with Salty Shrimp GH/KH+ to about 185-200TDS

Amount of water in the tank: 45l ( 11.89 gallons )
Weekly water change of 10l ( 2.64 gallon )

Pump: Eheim Compacton 600

Substrate: Ada Bacter 100, Tropica Substrate capped off with Flourite Black Sand
Decorations: 1 large piece of Corbo Root + 3 pieces of Wild Rhino Stone

So far the cycle isnt fully complete yet, im using Dr. Tim's Ammonium Chloride, getting around 2ppm ammonia and 1.5 ppm nitrite converted to nitrates in 24h ( is 2ppm enough for this tank size and stock id like to keep ? )

I "pimped" out the filter chambers with some 3D printed mods i bought on Etsy ( ill add links to these )

Using coarse foam at the filter intakes, then theres a medium coarse foam followed by some filter floss and 3 small media chambers filled with Biohome Gravel in the 1st compartment.

In the second compartment a media basket holding Biohome Ultimate and Biohome Gravel, in total there is around 1kg of media ( 2.2 lbs ) in the tank.

Taiwan Moss
Buce Kedagang
Buce Bukit Kalem
Buce Brownie Purple
Anubias Petite
Monte Carlo
Staurogyne Repens
Hygrophila Siamensis 53B
Rotala Rotundifolia H'ra
Limnophila Australis
Ludwigia Palustris Super Red

Are these to many plants for this tank?

Products i use:

- Easylife Easystart ( first 2 weeks at startup and after monthly filter cleaning )
- Tropica Premium or Advanced Nutrition ( every 2nd day 1 pump )
- Flourish Phosphorus ( if i dont use tropica advanced nutrition as the premium version doesnt have Nitrate - Phosphorus )
- Root tabs
- API Freshwater Master Test Kit

English is my 3rd language, apoligies if i made some spelling mistakes.

Thanks in advance,

Last edited:
Hi James and welcome to the forum :)

What are the tank dimensions (length x width x height)?

You don't want the pH to fluctuate. If the pH is fluctuating during the day & night, it can harm the fish. I would suggest reducing the CO2 a little bit and monitoring the pH over a week or two. If the pH settles down that is good, but if it keeps fluctuating, reduce the CO2 a little more. You should be able to have a stable pH while using CO2 if you have sufficient carbonate hardness (KH). If you have 4dKH and the pH is still dropping after you have reduced the CO2 a little bit, maybe increase the KH a bit to 6 or 7dKH and see if it helps.

If you post a picture of the entire aquarium, we can see how many plants there are and if there is sufficient open water and swimming space for the fish.
The tank looks nice :)

The only issue I have is with the length of the tank. If it was 2 foot long (24 inches) I would say no problems at all. The tank is only 16 inches long and that is going to restrict the amount of space the fish have to swim. You could keep 10 in there but you would have to see how they behave. If they act stressed or argue, they will need a bigger tank. And I would increase the size of the water change to 50% each week instead of 25%.
Top Bottom