Algae Slowly Covering My Sand

[yabadaba]

Hi, my new tank is in the process of cycling and that seems to be progressing well, but over the last few days brown algae has started covering the surface layer of sand. Would stirring the sand a little on a regular basis be the best way to cure/prevent this? I haven't touched it since I first set the aquarium up.

 

[Curiosity101]

If you're fishless cycling then just leave it. Just sounds like diatoms, or brown algae.

Also if you're doing a fishless cycle (with no plants) you might want to consider covering the tank sides with black binliners or something to block out all light. This way algae can't grow.

 

[yabadaba]

If you're fishless cycling then just leave it. Just sounds like diatoms, or brown algae.

Also if you're doing a fishless cycle (with no plants) you might want to consider covering the tank sides with black binliners or something to block out all light. This way algae can't grow.

Thanks for the response. I am doing a fishless cycle and it is brown, so it's probably as you say. However, I do have a few plants in the tank that are currently doing well, so maybe I should just look to reduce the amount of time the lights are on for?

By the way, another reason why I was thinking of stirring the sand is that over the last couple of weeks the water flow seems to have gradually shaped the sands surface so that it looks like waves. That looks quite nice and certainly natural, but there's one area at the front of the tank where so much sand has been moved that a patch of the aquarium glass is now visible. I guess (or hope) this effect will diminish when I have more plants/wood/rocks in the tank to break up the flow a little?

 

[Curiosity101]

Hmm, yeah I guess you might just have to cut down on light.

And yeah you could always stir the sand up, you should find it doesn't get pushed around as much once the tank is filled. But I still have a corner which slowly erodes away (if you can call it that) over time.

 

[waterdrop]

Since light plus ammonia is the formula for algae, and fishless cycling requires lots of ammonia, light is your only "control" over the algae, more or less. A number of the planted folks have mentioned that they start as low as 4 hours of light a day in a new tank and only very gradually work the time periods upward if they are not getting algae. I forget, what are your watts per gallon and your hours of light per day?

~~waterdrop~~

 

[yabadaba]

Since light plus ammonia is the formula for algae, and fishless cycling requires lots of ammonia, light is your only "control" over the algae, more or less. A number of the planted folks have mentioned that they start as low as 4 hours of light a day in a new tank and only very gradually work the time periods upward if they are not getting algae. I forget, what are your watts per gallon and your hours of light per day?

~~waterdrop~~

I've got 2 x 58w Arcadia Freshwater T8 lamps and the tank is 109 UK gallons (131 US gallons). Not sure what that my watts per gallon are as I'm not sure if it's based on US or UK gallons and on what type of tube (T8, T5?). I was initially leaving the lights on for about 14hrs per day on the basis that there wasn't a hint of algae at first, but I'm now reducing that to about 6-7hrs. Thanks for the reply.

 

[waterdrop]

Oh, that's your problem then, 14 hours is way too long. Your 6-7 that you're doing now is much more reasonable. If you want to see the tank with lights on and are home only morning and evening then get a couple of cheap lamp timers and let them give the tank a "siesta" during the middle of the day.

OK, about the watts/gallon: (take this with a grain of salt - there are others here who know different parts of this better than me)... I think the old "watts/gallon" guideline was based on T-8 tubes (T-12 give off more light per foot, T5 (compact) give off less per foot but are typically looped around more thus giving more total light (per a recent post by OM47)) and the gallons are indeed US gallons. This said, its important to know that this guideline breaks down for small and large tanks (like yours) (ie. it only works for middle sized tanks) Anyway, setting that aside, because I don't think its important at the moment, I'd say there's enough info to assume you only have enough light there for a "low-light" approach to plants (maybe even too low but that part I don't know) and regardless of that I think its clear that the algae is from too many hours combined with the cycling.

~~waterdrop~~

 

[yabadaba]

Oh, that's your problem then, 14 hours is way too long. Your 6-7 that you're doing now is much more reasonable. If you want to see the tank with lights on and are home only morning and evening then get a couple of cheap lamp timers and let them give the tank a "siesta" during the middle of the day.

OK, about the watts/gallon: (take this with a grain of salt - there are others here who know different parts of this better than me)... I think the old "watts/gallon" guideline was based on T-8 tubes (T-12 give off more light per foot, T5 (compact) give off less per foot but are typically looped around more thus giving more total light (per a recent post by OM47)) and the gallons are indeed US gallons. This said, its important to know that this guideline breaks down for small and large tanks (like yours) (ie. it only works for middle sized tanks) Anyway, setting that aside, because I don't think its important at the moment, I'd say there's enough info to assume you only have enough light there for a "low-light" approach to plants (maybe even too low but that part I don't know) and regardless of that I think its clear that the algae is from too many hours combined with the cycling.

~~waterdrop~~

Thanks for that. I was turning that lights on at about 8am before leaving for work and turning them off at about 10pm, but I'm now getting my son to switch them on at about 4pm when he gets in from school. Hopefully, the algae and not my plants will start to suffer, especially as autumn/winter hits and the amount of natural daylight in the room decreases too.

 

[waterdrop]

Yup, that's when my timers turn my lights back on, about 4pm after my son has come home from school (its -his- tank after all! lol) ...I'm going to assume the tank you are talking about here is the one you have been fishless cycling for about 2 weeks that I saw in one of your other threads. In that thread I saw that you used matue media and were already into having a "nitrite spike" so you are fairly far along in the process. I find that once you get out to that stage and beyond its not necessarily a bad thing to do some weekend water changing. Now normally we do these only when someone's pH is headed down toward 6.2 and lower and we want the tap water to pull the pH back upward, but in your case it might be useful to help get excess algae spores out of there. Its actually good practice for after you have fish and start to do normal tank maintenance. You use a gravel-cleaning siphon and clean the gravel (yes, even though there aren't any fish in there.. because the excess nitrites and nitrates seem to hang closer to the gravel) and take most (90% - down to the gravel is usual) of the water out of there, depending on convenience.) Then you replace it with conditioned, roughly temperature matched (just to keep your bacteria happily going full speed) tap water and recharge your ammonia back to 3 to 5ppm, whatever you were doing before. Besides lowering the hours of light, doing a clean of the glass and decorations before the water change and then having the water change hopefully take some of the algae itself and its spores out of the tank is a way to reset the algae to a lower presence from which you hope it will have a harder time coming back because you are now doing significantly less light time. As far as the fishless cycle itself goes, doing a water change is a mixed bag. Sometimes it seems to slow the bacteria for a day or two, but often it seems to kickstart them into going a little faster after that and it clearly refreshed the calcium that they like to get from the tap water. The bacteria themselves are not disturbed of course because they mostly live tightly bound to the biomedia in the fitlter. The act of moving the siphon around should also stir up your sand even more so that any surface algae gets mixed under.

~~waterdrop~~

 

[yabadaba]

Thanks for that waterdrop, much appreciated. Yes, it is my new tank that is currently cycling that I'm talking about and I'll probably try your suggestion of doing a large water change, followed by a re-dosing of ammonia, either tomorrow or on the weekend.