Flake food and cyanobactria.

[TrevP]

oops just realised this was not the place to post this so sorry for that.

Hi all,

I have been keeping fish for 25 years now and every so often I would get and outbreak of cyanobacteria( Blue green Algea) but could never quite get why they happened, recently though I just had another problem with it(still trying to get rid of it).

For the last couple years or so I have just been feeding my fish frozen food and everythings been great fish look really healthy and tanks been looking great but, just say the last month I started feeding flake food again and my tank has exploded with cyanobacteria. Nothing else has changed same water changes every week just the food change. so just wondered if anyone else has had similar issues or whether flake food is known to cause any issues. Maybe its just I have fed to much and should cut back , anyway thought I would ask the question for you to discuss!

Trev

 

[Byron]

It is not what food you are feeding, but too much of it. Or insufficient tank maintenance. Or both. I will explain how to deal with this, on the assumption it is actually cyanobacteria (a greenish slime that very easily comes off with your fingertips), some call it blue-green algae but it is a bacteria. A photo will confirm.

Cyanobacteria is caused by organics, in the presence of light. Too much organic matter can occur from overstocking, over feeding, insufficient water changes, not keeping the filter media well rinsed/cleaned, allowing the substrate to get clogged with detritus and mulm. Any one or more of these conditions can cause cyanobacteria.

The only safe and effective way to deal with it is to restore a biological balance. Nitrates usually increase with this, but not always. I had this twice (in the same tank) several years ago. Both times I stopped using plant additives (which forces plants to use the natural organics more), I did large water changes (once a week, but twice is OK, provided the parameters [GH, pH and temperature] of the tank water and tap water are reasonably the same), removing as much of it as I could [rub it off surfaces, it will sink and is easy to vacuum up), cleaning the filter at every water change to get rid of the organic sludge, and feeding minimally. Fish do not need food every day, they can manage perfectly well with anything down to once a week. I do not advocate light blackouts, as without solving the organics issue it will come back again, plus you want the plants (assuming you have live plants) using more of the natural nutrients and this means they need light to photosynthesize. Floating plants can help with this as they are fast growers and thus need/use more nutrients and dissolved organics.

 

[Guest14017]

Are you certain it's cyanobacteria? This is rare in tanks, it's more of a pond problem. It can kill fish. Do you have any pictures of the condition.

 

[Myraan]

If I feed too many flakes I get an oily film on the surface. My worry is that these organics are coming straight from the flakes and never even have a chance to create organics in the form of fish poo. Which seems inefficient and overall would lead to extra organics.

Does anyone have thoughts on this? Because organics are organics from overfeeding whether they are floating the surface or not.