Yup, I bet its the cold water....its amazing the difference warm water makes, lemme tell ya....
Definitely get the heater replaced, and I bet he'll go back to normal.
I'm a little confused by what you said though....are you planning to cycle or leave it uncycled? O.o
If you don't plan on cycling(which it sounds like you're not, which is totally fine if you want to keep up with the water changes)then you will need to do at least one 100% water change a week to remove the ammonia that, in a cycled tank, would be broken down by the beneficial bacteria. Only doing partial changes in an uncycled tank will just dilute the ammonia....and it will eventually build up.
Its quite funny isn't it, how you become so unexpectedly attached to a little critter you wouldn't expect to become attached to. I'm really not sure where the whole myth about bettas, or fish in general being easy to keep and somewhat boring/uninteresting pets started up.....They're such personable and fun pets, a lot smarter then people give them credit for too.....they can even be trained to swim through hoops and such. I've even read about someone training their females to know their names.
They're such a joy....though a little expensive to keep properly xD Its worth it really, I think at least.
I do realize that I will have to do 100% changes on some frequency, though some people have suggested to do 80% changes so that you can still leave the fish in the tank. Since I was going to do 100% changes 1ce/week with a 1 gallon tank, I figured that 100% once/2 weeks (or possibly up to a month) would be OK with a 5 gallon, of course with 2ce/week 50% changes.
I did just have another thought about the cause of Martin's problems. Around the same time that my fish started showing change in behaviour, we started using eucalyptus in the room at night. (The tank is in my son's bedroom and he has a cough). I just realized that eucalyptus (which clears out the mucus in your lungs) is probably not so good (understatement?) for an air breathing fish! Also, since I am turning off the tank's light at night, the air in the tank is probably cooling, and thus contracting, and thus sucking in some of the room air which has eucalyptus in it. Anyone have thoughts on this? Am I being crazy?
Also, tonight as we were getting ready for bed (bedtime stories), Martin started swimming rapidly around his tank, almost freaking out, after hardly moving for days ... and I had just brought the eucalyptus oil into the room with a humidifier. Also, Martin didn't eat tonight, first time that has ever happened.
Nothing I can do about this now as my son is already asleep. Hopefully Martin will make it through the night and I can move his tank in the morning.
Despite its larger size, I'd still suggest one 100% a week.....at the very least, you may be able to get away with every two weeks, but you'll want to do more frequent partial changes in between. I wouldn't go longer then two weeks though.
The problem with the 80% change though is that, in an uncycled tank, thats not going to completely remove the ammonia....the only way to do that is with a 100% change.
From my personal experience, I really don't think the now recommended 1 50% and 1 100% change is enough for a 1 gallon....there are people who would argue that, and do have a reason for that schedule, but it goes agaist what I learned when I first started, plus what I've been doing ever since and I have a hard time believing I've been doing it wrong all this time...
But, I think I said this earlier...water changes tend to be a highly debated topic; everyone has their own opinion. Best way to find out what works best(at the least for you and your fish and tank)is to actually get an ammonia test kit(liquid)and test yourself, then preform water changes accordingly.
You know, I don't know about the Eucalyptus; whether its harmful or not O.o I've never heard anything about it in relation to bettas before.
I suppose it would never hurt to remove him from the room in the morning, just to be safe....but I honestly have no idea about that, its very possible I suppose....
He didn't make it through the night. Poor little guy.
We will try again with a new fish in a few days ... but this time I will make sure that we have a functioning heater BEFORE getting the fish (and maybe a filter) and I won't keep him in the room if we are doing eucalyptus steaming!
:( I'm sorry for your loss. Right before my Gunter passed away, he started swimming rapidly after not really moving for a day. He was very sick with columnaris, and it could be that Martin had a touch of something that was exacerbated by the stress of changing tanks again or the sudden drop of temperature. The weather did the same thing here, and I now have a sore throat. It seems fish and humans may not be as different as we think.
Oh no! I'm so very sorry for your loss :(
It is very possible that he may have had something even before you purchased him that just came to the surface because of a little stress....I have had that happen before. I get a fish home thinking its all nice and healthy, get him into a nice, clean, warm, properly-sized...and all of a sudden somethings wrong and he passes away. Bettas are hardy little fish, but how they are kept in petstores in those terrible conditions, you never know what could be going on inside them.
I wish you the best of luck with you're new fishy friend, whenever you decide to get him :)
thats one of the places the good bacteria hang out. I have a 45 gallon filter with a nice baffle to keep the water smooth and it does 200 gallons an hour. My tank is only 20. So it moves that water 20 times an hour past the good bacteria. Need a filter and good heater. I keep it at 80 24X7. Going from 76 to 80 in my mind will add a very very good spring to his step! IMHO
But I just know what works for me. The cory cats thrive at this temp it seems too.