Algae while cycling?

I'm surprised you still have NH3 and NO2 at the end of four weeks; if all I knew was that you were on week four, had 10ppm NO3 and algae, I'd say you were through cycling. If you've been changing the water daily, unless your tap water is high in phosphates, I can't imagine that your phosphates have built up to a very high level. Unfortunately, as far as I know, there will always be SOME algae in any healthy tank. Where there even low nitrates, phosphates and light, you're going to see a bit of algae.

If you've been over-cleaning the filter, this could be what's stopping you from reaching the end of the cycle. Sometimes people inadvertently remove the very bacteria they're trying to colonise by removing media from the filter or rinsing it under the tap, when really the only thing you ever want to do to a piece of biological filter media is rinse it out in a bucket full of water from the tank.

Can you post more details? Did you experience the expected 'spikes' of ammonia and nitrite? What kind of filtration are you using? Which specific type of filter, and what's the flow rate/model? When you change the water do you vacuum the substrate? Are your danios large? (Giant danios get pretty big, it could be that having six of them is overwhelming your filter).

Knowing the answers to these questions will us to help you figure out what's happening in your tank. If you want to post all your tank's parameters only once, there is a section of this forum called 'members' aquarium specs' where you can create a post with all your tank's info and create a link to put in your signature so people can click on it and read all the details.

As for the algae, once you're done cycling, you might want to get some otocinclus catfish; they stay very small, are harmless to other fish and do an amazing job of cleaning up algae. I almost never have to wipe down any surface or decorations in my tanks, there are only 2 in my 20g and 3 in my 45g and they keep the tanks sparkling clean.

Hopefully you'll be over the uphill cycling battle soon, it just gets easier from then on in. Welcome to the most addictive hobby on Earth

Ammonia + water + light = algea, furthermore algea is part of any fish only tank, and usually a battle with any new tank. ammonia is the prefferred source of N for plants, phosphates have been blamed for algea growth for years but some very knowledgeable people here contend that ammonia is more likely the cause. in either regard, 1 ppm of ammonia or nitrite is really high for fish, so I'd try to reduce the levels a bit until the bacteria takes over. blackouts will kill the algea, or you can take out the plastic plants and dip them in a 1-19 bleach solution then rinse well and put them back in. My Experience with fish only tanks is pretty substantial, and algea is a battle at all times, go with as little light as you can stand, for as short a period as you can stand, and keep up on good maintenance. other than that the occasional scub or blackout is the best plan. I also agree that your cycle should be wrapping up, but with fishy cycling there seems to be a lot of variables.
dave

The brown algae is really diatom growth, and it is not uncommon in newer tanks. I wouldn't worry about it while you're cycling, because the last thing you want is to change something that might affect the cycle.

After the cycle has completed, if the diatoms don't go away on their own, you can try increasing the light (diatoms don't grow well in bright light) or you can gets some otto cats, who will clear it quickly.

All my new tanks have undergone the diatom stage and it has generally passed on its own.

HTH,
Jim

Agreed, don't worry about it just yet. My current tank went through a few stages of alga, starting with diatoms (brown algae) and right now I'm fighting a strain of hair algae. Worry about getting your tank cycled first. Once things have settled down and your tank's come to equilibrium, I expect that things like algae will be a little more manageable.

I do agree that Oto's are neat fish. They're a lot of fun to watch and they are diligent workers, very good with soft algae. But they won't do well in a cycling tank, nor should you get them, solely based on algae, unless they fit into your stocking plan.

Try increasing your water changes to twice daily instead of increasing the size of the once a day change. More frequent, but smaller changes will be far more effective in preventing a buildup.

Sounds like everything you're doing is perfect. If you're into the nitrite spike, you'll be over the cycle soon. Once you are fully cycled a couple otos will take care of the algae and keep your tank looking new
P.S. you know you're addicted when you play hookey from work to chat on a fish forum...

Danio's are about as indestructable as a fish gets, My first choice when I used to do fishy cycles.

I didn't realize that algae would feed on Ammonia, so that is surely the source of the problem.

Click to expand...

I learned much of this recently while doing my fishless cycle, according to some real experts at this site and others, ammonia is the preffered source of nitrogen for most if not all plants, that is one of the reasons the silent cycle works well. I learned after putting plants in during my fishless that a high ammonia level will promote the growth of every type of algea known to man ( I may have even cultured a few new specimens). In another thread I posted about Phosphate in my tap water, Tom Barr ( I hope I'm not misquoting him here) stated that he didn't feel P was the cause of a lot of algea growth but rather N via ammonia,He suggested that he had High P in his tanks but didn't have algea, and that if you set up control tanks one with high P one with amonia, the ammonia tank would be the one that greww algea. I can't present the case nearly as well as he did, But have found him to be a constant source of accurate information, as well as someone who diffuses popular myth with real science pretty regularly. I have every intention of doing the exact experiment he suggested. I Seriously doubt that my experiments will yeild anything different than Mr. Barrs did, but love to prove things to myself the hard way.
dave