I've had a tropical fishtank for about 1 1/2 years now, 25 litres heated to 26*C currently with a couple of plants, a red betta, 4 cardinals & a tetra (I think) which I acquired by accident and have never been able to identify.
The problem is in September I'm going to uni, and I need to make sure the tank's as low maintenance as possible. I'd quite like to buy a few otos to keep the plants a little more algae free anyway, but I'm conscious the tank's not going to have many water changes, and I'm not sure how much I trust my family to feed the fish every day while I'm not there either.
The fish have survived a week without food several times when I've been away - but that's probably not done them much good.
I'm also worried because the fish I haven't identified has been getting increasingly aggressive - and the betta's been quite lethargic for a while now.
So I guess I'm asking:
a) does my tank have any spare capacity for more fish
b) would buying some java moss or another low light plant help keep the water in a decent state for longer between water changes (it always gives min. ammonia, nitrates & nitrites in tests nowadays)
c) any suggestions for keeping the tank ticking over while you're away for extended periods of time? (I already have the light on a timer..)
d) and any ideas what might be wrong with Yossarian? (the betta)
Ooh also I'll try and take a decent picture of the unidentified fish in case anyone can identify it: it is about the same size as the cardinals, with the same eyes, you can see it's silver at the front and you can see its spine, the fins are largely clear and it spends most of its time at the top of the tank, is quite active and greedy at feeding time, swims differently to the cardinals.