NatalieHurrell
Member
Hi all,
Sorry this is a such a long post, but I've hit my first little problem with my current tank and need some assistance please. I've started to get cyanobacteria under the substrate. The brown, rusty patches appeared first and I assumed it was iron from Tropica tabs. The cyano is about 1cm under the top of the substrate at it's highest point and a vivid blue green. I can find loads of info on cyno above substrate, but not below.
Tank is as per journal Grownup Swedish Suprise:
*Pond soil, coarse sand and pea gravel in net bags under 2" coarse sand
*Fluval Aquasky programmed at 50% white, 35% green, 30% red and 8% blue. 1 hrs sunrise and sunset, 5 hours daylight
The cyno started to appear two days ago. Possible reasons I can see are:
1) The tank gets no direct sunlight, but the growth has started at the end nearest the French doors (on lefthandside) and half of the front on the tank, also nearest the doors, so could be sunlight related. We do keep the curtains pulled at that end of the room until late morning on bright days though
2) I swapped my spray bar out for a duck bill about four weeks ago, in an effort to declutter the tank. The spray bar had been positioned to hit the front glass, so might be reduced flow to the substrate? Spray bar back in the tank now
3) Lack of nitrate - I don't think it will be lack of nitrate, but please correct me if I'm wrong. I dose Aquadip Plant Fertiliser Plus at 15ml three times a week and my tap water has 40ppm of nitrates (albeit only tested with an API Master Test Kit, but this also agrees with the latest Southern Water report). Tropica Nutrition Tabs at strategic points. However, I did stick a couple more Tropica Nutrition capsules in a week ago, so could it be higher phosphates? I added them to the area with the Cryptocoryne Lutea Hobbit and the Brazilian Pennywort, as it's never really taken off, but I realise these are not really root hungry plants like Amazon Swords. The cyano has appeared near these two areas. Have I made a mistake here? Bottle of TNC complete on it's way to me and also looking into EI dosing
Other questions:
1) As the cyano is only under the substrate I have so far only blacked out the end nearest the doors and the bottom half of the tank around the rest of it and killed the lights for a couple days (whilst stopping feeding fish and dosing ferts). I started putting the light on at a low setting for two hours yesterday, as am aware the plants could start to suffer and algae might appear shortly after. Will I get away with this or do I need to cover the whole tank and do a total blackout if it's only under the substrate?
2) The only other time I have had cyno in 40 years of fishkeeping it was also under the substrate and I was given some tablets to push into the gravel by a friend. It disappeared within an hour or so. I'm going back about 25 years here, so no idea if you can buy anything similar these days? Either way, would rather get the source of the issue if I can. Would potassium nitrate see it off?
3) Can cyano "escape" if I pull a plant up for instance? I know all tanks likely have it at microscopic levels anyway, so conditions may just not be suitable for it above the substrate?
4) Having zoomed in in the photo I am wondering if there are tiny airpockets left, despite stabbing the substrate with my tweezers on setting the tank up and having Malaysian Trumpet Snails. These areas have barely any plants in them, but are no deeper than 3". I only have sand round the edges of the tank for asthetic reasons. Should I just plant into those areas, so that there is competition for the cyano and increased water flow with the plant roots?
Thanks if you have managed to read this far and for any assistance you may give.
Nat.
Sorry this is a such a long post, but I've hit my first little problem with my current tank and need some assistance please. I've started to get cyanobacteria under the substrate. The brown, rusty patches appeared first and I assumed it was iron from Tropica tabs. The cyano is about 1cm under the top of the substrate at it's highest point and a vivid blue green. I can find loads of info on cyno above substrate, but not below.
Tank is as per journal Grownup Swedish Suprise:
- 900 x 50 x 48h low iron rimless - physical water volume approx. 170lts
- Freshwater temperate (22 degrees), with 6 Corys, 14 male guppies and 16 or some cherry and amano shrimp, Malaysian Trumpet Snails and Ramshorns. Good population, but they are not taking over
- Fish fed very lightly twice a day
- 50% of substrate planted with mainly fast growing stems, plus a load more epiphytes, floating water lettuce and riparium plants (Parlour Palm, Peace Lily, Fittonia, Tradescantia, Water Mint). All growing well
*Pond soil, coarse sand and pea gravel in net bags under 2" coarse sand
*Fluval Aquasky programmed at 50% white, 35% green, 30% red and 8% blue. 1 hrs sunrise and sunset, 5 hours daylight
- Tank has been setup since mid-March and I used seeded media, no blip of Ammonia or Nitrite when I tested over the first three weeks. Nitrates read 20-40ppm, but have since added floaters and riparium plants. Stopped testing now, as we all know home test kits aren't exactly reliable
- No algae (other than diatoms on week 3) and minimal detritus
- 50% water changes every 10-14 days
The cyno started to appear two days ago. Possible reasons I can see are:
1) The tank gets no direct sunlight, but the growth has started at the end nearest the French doors (on lefthandside) and half of the front on the tank, also nearest the doors, so could be sunlight related. We do keep the curtains pulled at that end of the room until late morning on bright days though
2) I swapped my spray bar out for a duck bill about four weeks ago, in an effort to declutter the tank. The spray bar had been positioned to hit the front glass, so might be reduced flow to the substrate? Spray bar back in the tank now
3) Lack of nitrate - I don't think it will be lack of nitrate, but please correct me if I'm wrong. I dose Aquadip Plant Fertiliser Plus at 15ml three times a week and my tap water has 40ppm of nitrates (albeit only tested with an API Master Test Kit, but this also agrees with the latest Southern Water report). Tropica Nutrition Tabs at strategic points. However, I did stick a couple more Tropica Nutrition capsules in a week ago, so could it be higher phosphates? I added them to the area with the Cryptocoryne Lutea Hobbit and the Brazilian Pennywort, as it's never really taken off, but I realise these are not really root hungry plants like Amazon Swords. The cyano has appeared near these two areas. Have I made a mistake here? Bottle of TNC complete on it's way to me and also looking into EI dosing
Other questions:
1) As the cyano is only under the substrate I have so far only blacked out the end nearest the doors and the bottom half of the tank around the rest of it and killed the lights for a couple days (whilst stopping feeding fish and dosing ferts). I started putting the light on at a low setting for two hours yesterday, as am aware the plants could start to suffer and algae might appear shortly after. Will I get away with this or do I need to cover the whole tank and do a total blackout if it's only under the substrate?
2) The only other time I have had cyno in 40 years of fishkeeping it was also under the substrate and I was given some tablets to push into the gravel by a friend. It disappeared within an hour or so. I'm going back about 25 years here, so no idea if you can buy anything similar these days? Either way, would rather get the source of the issue if I can. Would potassium nitrate see it off?
3) Can cyano "escape" if I pull a plant up for instance? I know all tanks likely have it at microscopic levels anyway, so conditions may just not be suitable for it above the substrate?
4) Having zoomed in in the photo I am wondering if there are tiny airpockets left, despite stabbing the substrate with my tweezers on setting the tank up and having Malaysian Trumpet Snails. These areas have barely any plants in them, but are no deeper than 3". I only have sand round the edges of the tank for asthetic reasons. Should I just plant into those areas, so that there is competition for the cyano and increased water flow with the plant roots?
Thanks if you have managed to read this far and for any assistance you may give.
Nat.
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