Thank you for filling the form out, it makes it so much easier for us to help you diagnose your fish
There are a few red flags that pop up when reading over the data you've given us, I'd like to point those out as possible causes, if I may. Please note that while the below may highlight various issues, it is important that I bring them up as any individual thing
or all of the things
that I describe could be contributing to the decline in activity in your fish and could potentially lead to death.
The first issue is tank size
; a 1 gallon aquarium has been said by many to provide a suitable permanent home for a betta, while not my own personal choice I respect what others have said and definitely recommend at least a 1 gallon aquarium per fish
. Anything less than 2.5 gallons can be incredibly difficult to heat so 2.5 gallons would be even better.
The second issue is your 4 gallon; 5 fish in an unfiltered 4 gallon aquarium will likely have consistently high ammonia readings which can cause sickness and death. I think it's great that you have 5 females; this is a good number to have together as it distributes fighting within the 'pack' evenly and thus helps prevent a single female being singled out. This community of females is often referred to as a sorority and should be in a minimum of a 10 gallon aquarium that is very densely planted
. The plants help break the line of sight and offer the females a place to escape to should they become stressed or intimidated by the other animals in the aquarium or activity on the outside.
The third issue is regarding water changes
. Unfiltered, uncycled aquariums that are between 1 and 5 gallons with a single fish should receive two water changes per week: one 50% and one 100% (the 100% should also include a thorough cleaning of tank walls, decorations and substrate). This keeps ammonia levels in the safe zone (i.e. at or close to 0) and reduces the risk of disease. A betta in a healthy aquarium should seldom get sick. With regards to your 5 females in the 4 gallon I can't make any recommendations as I honestly do not believe this to be at all safe and would implore you to upgrade to a 10 gallon or give your ladies individual aquariums.
The fourth issue is the lack of heating
. While it may be warm where you live you at least need a thermometer in each aquarium so you can accurately and safely read the temperature. A strip thermometer on the oustide of an aquarium isn't very reliable so one that is adorned with a suction cup, designed for use within
the aquarium is definitely recommended. Betta spledens
need to be kept within the 78 - 82F range, with 80F being ideal. In a standard household setting, the water temperature of your aquariums will be a few degrees lower than the air temperature.
It is also important to highlight the necessity of consistency
when it comes to heat. Temperatures often drop at night and the fluctuations can cause stress, immune system failure, disease and death amongst fish -- not just bettas. It is very important that your fish have a consistent temperature, even if it is below the recommended range for bettas. Aquarium heaters
provide this by gradually heating the water to the set temperature (some have an in-built thermostat whereas others can be adjusted to your desired temperature); heaters are designed to detect the temperature of the water and they will switch off once they have heated the water to the set temperature; they'll switch back on once it drops a degree or two below what it is supposed to be.
With the above considered and hopefully with a few more contributions from other memebrs we can continue to rule out the cause of your fishes' troubles and make them feel better.