Guppies can stay alive quite well actually, if they die it just means
a) you got bad stock
b) your setup needs to be improved.

If you buy from a shop that stocks a whole bunch of guppy in a tank, they could actually already be of weak condition. You can always expect some of those you purchase to die off pretty soon.

I haven't been keeping fish for a while, no idea where's good in PJ.

Just went to Pet Lover Center in Ikano, the guppy stock looks good. Fins are not worn and the amount of fish per tank looks alright.

Bear in mind that you should avoid mixing male + female guppies in a tank if possible, or if you do then make sure ratio is like 2:1 or something, 1:1 ratio is no good.

The males will always harass females for mating.

Sorry for not making it more clear - as mentioned, male harass female, so you'll need more female than male. ideally no less than 2 female to 1 male, the more the less stress.

tehoice you sell pure strain guppies?

anyway guppies don't like strong water flow, for small tanks and using HOB filter, please take note of how the water falls.

did you know that bigger tank is more newbie friendly than small tanks?

Bigger tanks cost more but they're less susceptible to sudden changes like say temperature or chemical composition.

HOB filters, even the small ones can produce quite some current in small tanks.

Just look at your guppies, if they're struggling then it's not good. If they're relaxed and can stay stationary then it's fine.

Even if your HOB filter intake reaches the bottom, it doesn't clean all those other areas.

That's why there's gravel filter (plastic base, place at bottom) but gravel filter can be dangerous, especially if you're using small gravel where fish can dig, some do get stuck in such filter.

Easiest is to get that type of tube where it sucks the debris from the gravel. I wouldn't be too picky about the dirt on the gravel though.

I hope you are aware of the male to female ratio when it comes to guppy breeding.

The female's going to be stressed silly la. It's supposed to be 1 male to 2 ratio.

How many % of the water do you change? (What's your tank size btw?)

Anyway yes, correct that it's good to leave water as it is for a while for chlorine to be removed. Need not be a tank, just a large pail will do. Pump not necessary though, just leave it overnight will work.

Changing tank water ever day / 2 days isn't good either, water changing can stress the fish and it also the chemical properties keep going through changes.

Just change 10% - 20% water every week or so would be fine, that also depends on what's the stock like in your tank.

If you feed a lot then it's not surprising you're changing water like that. Even if the fish doesn't contaminate the water, the food does.

There's not hard and fast rule but 10% - 20% water change per week is the general practice. In your case, small tanks so it's easy.

2ft tank onwards - not so easy to change 50% every day.

As for the air pump, it's about water movement rather than the pump itself. If you put the pail at a reasonably airy area then it will do fine.

The only time that I try to change water on daily basis is for Betta, their fins curl once it past certain 2 days.

I used to have Crowntails, but they curl damn fast. In the end go with HMPK.

The fishie stuff I had - MANY. Gave away my 4ft tank already, 3ft tank broke and cost me thousands as my imported fish all KO. Many ups and downs. Still love the hobby, just don't the luxury to continue.

I have 1ft tank before. I can do that any time but small tank less forgiving.

I prefer to have at least 2ft tank.