Well Goldfish deffinitly need cycled water, not only for the filtration ( they are the dirtiest fish ) but also because they need oxigenated water, which the filter helps with, as well as a bubble system.
but Betta's have a Lymbrinth organ that allows them to breathe our air, without the needed bubble system. but also what i dont understand is nativly Betta's live in small rice fields, where the water is staginated. Dont they do better in water that does not have alot of current? iv had betta's before this one, and i have had this tank much longer than i have had him, and for months my betta's have done fine and then this happens. although i did not know that i needed to still do water changes weekly.
The tank might of experienced an ammonia or nitrIte spike which can be very unhealthy/deadly for fish depending on how high the levels are. (I was clueless with my first betta and petco told me if I had a filter I never had to change the water :shock: - never listen to petshop employees is rule numero uno)
It had to have been the ammonia spike. and i have to say that i also work at petco, i have for 3 years, but what we learn there is after getting tank -set up and running, let the water run with the filter for 7-10 days. that gets the nitrogen cycle started. come back with a water sample which we test the water for free, and see where the levels are. if everything seems good then we recomend the customer get 2 or 3 fish to start out ( depending on the size tank they start with ). and do another water sample 3 weeks after, assuming all goes well. ultimitly tho it all depends on the size of the tank. not all employees are bad we just do not get all the information. but iv always recomended even with betta's to get the tanks with the filter, even if its a 2 gal. but i usually recomend tanks larger than 1 gal. Aqueon tanks of the best ( quote quote ) kits that we sell. and we now carry heaters for even the smallest of tanks. iv learned to be careful that information that i hear.
infact i have one co-worker who only changes her Betta water every 6 months, a 2.5 gal without a filter! i really do not know how her betta is still alive. but she swears by this care, no matter what anyone says. i cant get her to change her mind.
anyways what wattage heater should i get for my 5 gal? when i already have a 50 watt thats not doing the job. not a 100 watt right?