Water Change Question

[soritan]

So... I feel kinda stupid for asking this. I know that the general advice given to people who have a 10g tank is, 20-50% every week... and today is generally the day that I change my water (I normally do 25%, 2.5gallons, simply because I have a 2.5g bowl and it's easier)... but for curiosity's sake, I did a test of my water, across the board.

ammonia: 0
nitrites: 0
nitrates: 5

It's a planted tank, rather well lit... I thought that keeping my nitrates at 0 in a planted tank usually invited cyanobacteria? That around 5-10 nitrates was about right for plants?

Should I really be water changing every week if my test kits say that I'm in the clear? Should I go by the often suggested regime, or should I go by what my kits say? Are water changes in planted tanks handled differently?

Is there something I'm missing? I'd like to think that I was doing this correctly the whole time, but now I'm suddenly unsure...

 

[rdd1952]

Not really a stupid question at all. You should do a small water change just to vacuum up some waste. You will always have fish waste and some debris from the plants too. If those build up too much they could cause a problem with ammonia and nitrite later on. The nitrates definitely aren't high enough to warrant a big water change to lower them. Even in 10 gallon, I wouldn't do any more than you usually do at 2.5 gallon. I generally only change about 15 to 25 percent in my 2.5 and 5 gallons. Just what ever water I remove while vacuuming.

 

[soritan]

Thanks, that makes sense. I have some 1g bowls and could use those to help me do a 10% change. That should give me just enough time to vac up uneaten bloodworms. *nods*