Category Archives: Water

Battling blue green algae in your aquarium

Posted by on December 1, 2012 No comments

In July 2012 I noticed that something wasn’t right in my aquarium. I change the water in my freshwater aquarium regularly so it was a bit of a surprise to find algae in my tank as shown below.

The picture shows a bit of blue green algae or Cyanobacteria in my tank. I did regular water changes – a change between 2 to 3 weeks (which is plenty if you know my tank and if you live in Finland with good fresh water) so I knew it wasn’t because of that. It seems you can get blue green algae in your tank even if you change water regularly! I also hadn’t change the lighting conditions in the tank nor added new fish nor had I in my opinion changed my feeding habits either. Read more »

Water change obsession

Posted by on November 28, 2010 1 comment

Why do we change the water in our freshwater aquariums? Of course to keep the water clean from waste and ammonia derived toxics (NO2 and NO3). This is where hopefully all of us agree on when it comes to freshwater aquarium keeping. But the discussion starts when we talk about how often do we need to change the water in order to keep the readings low – and particularly with NO3, on what level.

On some forums, especially with visitors from North America, I hear a lot that I am crazy when I don’t change my water every week. I hear that I will get ammonia in my water, my nitrites levels will go sky high and all that. Well, my test kits don’t show me anything like that and I change my water every 4 weeks. Yes, not 1 but every 4 weeks. My test kits show me readings as follows: NO2 = 0, NO3 = 10-20, pH = 7.0. What would be the reasoning to change the water at this point?

I am not going to change the water, and by that affect the ecosystem, if I don’t get high nitrates or some nitrites levels. I don’t know if the water quality is just poor in North America (maybe not Canada, but how about California for example?) and because of that you have to change the water more frequently. But at least here in Finland we have very good tap water so this is not a reason to change the water.

Of course at some point you have to change the water even if the readings show normal numbers, since you want to gravel vacuum your tank. This would be the reason for me to change the water if the water value readings are ok. And for my tank the change frequency seems to be 4 weeks.

At this point it must always be said, that the water change frequency is always tank specific. Nobody can tell you how often you need to change the water in your tank. But please do that based on the water value readings and not based on some comment on some forum “Just because you should”.

Nitrites (NO2) and nitrates (NO3) in a freshwater aquarium

Posted by on November 28, 2010 21 comments

As I am writing this post, I am measuring the nitrates level (NO3) in our freshwater aquarium as I do at least once a week. My level today seems to be somewhere between 10 and 20 ppm. As it has been as long as I can remember.

Now, especially if you are from North America (based on my experience on some forums I visit) you might think “How come he says as long as I can remember?” or “OMG, you must change your water!”. For some reason on some forums, without mentioning any names, changing the water once a week is an obsession for some and having a level of 20 ppm nitrates in your tank is somehow crazy. Well, I disagree.

As you know, nitrites turn into nitrates through the nitrogen cycle. This is good. A well functioning freshwater aquarium has a level of 0 ppm of nitrites in the water. If this goes up, time to change the water and start thinking of the reasons why nitrites levels are up (dead fish in the water, too much feeding, old filter system.. or something else). But nitrates is different. Actually, to have nitrates in the water is good because of the plants. The plants need nitrates (actually they need either ammonia or nitrates, but you don’t want to have ammonia in your water. At all).

In my freshwater aquarium, I have plenty of plants. These plants will use the nitrates in the water for their growth and turn the wasteful nitrates into proteins – and more beautiful plants. It’s really like a good cycle; I get lower levels of nitrates and at the same time greater plants. And this has been going on for as long as I’ve had my Juwel RIO 180 tank. And there is no reason to believe that this would change either, so I am really hoping to have low nitrates levels from now on.

To summarize, I have 0 ppm nitrites and 10-20 ppm of nitrates and with the amount of fish and plants I currently have, this is a stable ecosystem. If either the number of fish goes up, or the number of plants go down this stable ecosystem will change. Only you can know when and if you have a stable ecosystem. With this kind of stable ecosystem you don’t necessarily need to change the water that often.

JBL test shows false high nitrite level

Posted by on October 17, 2010 1 comment

What would you do if you get a nitrite test result showing your nitrite levels are at 0.8-1.0 ppm? At least I would panic at first. Just take a look at the picture below and you see what I mean.JBL Nitrite test shows false positive

The result to the left is the one I got from my first sample and it got me panicking for a brief moment. It shows a nitrite test result as high as 1.0 ppm which basically means that my fish are about to die. At this point I was still wondering how this could have happened since only a while ago the results were fine. What could have happened?

Then I thought I better take another test just to verify the reading. That result is in the middle in the picture above. As you can see it looks normal. I confirmed this by measuring the nitrit level a third time and you can see the result of that one on the right. This also showed normal. What had happened? All of the tests above were taken withing 5 minutes of each other.

Well, when I took the first test for nitrite I also took a test for nitrate. I had the both test bottles in the same hand shaking them violently to have them mixed well. This is what the instructions for the JBL nitrate test says I should do – but the nitrite test does not say I should do this. Apparently if you shake the test bottle of JBL nitrite test too much, you will get a false positive reading as a result. I never thought that shaking the test bottle would cause any harm – I mean it was not explicitly forbidden or anything. But apparently you shouldn’t do that. Only gently see that the two different liquids you dropped into the water are mixed and leave it alone for three minutes.

Joined Aquarium Advice community

Posted by on October 16, 2010 No comments

I’ve been looking for sites on the Internet that would gather freshwater aquarium hobbyists together and also give advice to beginners. This hobby is so changing that you just can’t do it by only reading a book (but it of course helps a lot). Just as I have been writing about on this blog, there are many people giving different kinds of advice and in the end it all depends on your tank and what you have in it. So it is good to have someone to ask or share and exchange your own thoughts to others.

So today I today joined the Aquarium Advice community at http://www.aquariumadvice.com. I been a member for only a few hours, but already my initial post got many replies from people who really seem to understand this and know what they are saying. It feels nice to have a place to ask questions from and also share good moments. Already from this first day in the community I have to say that I changed again my opinion about water change frequency. It really makes sense to change the water quite often since in the nature the water is flowing and changing naturally, while in an aquarium it’s you who have to do the changes – so why not change it as it would in the nature. It really seems there is no harm in changing the water too often (that is, if you are not doing it daily – that would cause unnecessary stress to the fish :)) if you are careful with vacuuming the gravel too intensively. So I will probably follow the following pattern in water changes from now on: change 10-20% of the water weekly with light gravel vacuuming and once a month 30-40% water change with intense gravel vacuuming.