# Filamentous diatoms for 2 months, nothing helps



## HoneyGourami (3 Feb 2021)

Hello, I have a long term problem with filamentous diatoms, they appeared shortly after cycling my tank. People on FB groups confirmed it is 100% FD but no advice worked so I'm trying here. My water parameters: ph 7.1 ammonia 0, nitrite 0, nitrates 5-10. I have RO water that I partially mix with tap water. I tried everything from daily 50% water changes to reducing lights to enhancing my filter to introducing a crew of amano shrimps. It is just worse and worse every day, my plants are not visible if I don't manually remove it. My tank is heavily planted and plants seem very healthy and growing despite that. To clarify it is practically only on moss, other plants are almost fine, it is just so bad on moss that it is literally everywhere in the tank if it makes sense. 70l tank, co2 24/7 with autocontroller and bazooka diffuser, temperature 24C, superfish 28W light 5.5 hours a day, external canister filter and good water flow. Does anyone have any idea what to do? I'm at the point of regretting getting a tank, it is a pain to look at it. Feel free to ask for any additional info and thanks.


----------



## dw1305 (3 Feb 2021)

Hi all,
Welcome to UKAPS. It sounds like your plants are doing OK, which is honestly the most important thing.


HoneyGourami said:


> People on FB groups confirmed it is 100% FD


Yes, should be fairly easy to identify, brown in colour and gritty when you roll it between your fingers, because of the diatoms silica frustule. Have a look at our threads mentioning <"_Fragiliaria_ or _Synedra_">_._

The <"Green Algae_ Rhizoclonium_"> can also appear brownish, but it is smooth to the touch.


HoneyGourami said:


> to enhancing my filter


How have you pimped your filter?


HoneyGourami said:


> superfish 28W light 5.5 hours a day


I don't know the answer to the algae question, but I'd definitely go for a longer photo-period, probably 8 hours for starters. At the moment you have 18.5 hours of darkness, and no-one is going to persuade me that that is a good idea.

cheers Darrel


----------



## HoneyGourami (3 Feb 2021)

Hi Darrel,

Thank you! I cleaned it today without taking a pic but will try to take a picture tomorrow. The filter originally came with ceramic rings and bioballs, I added alfagrog. Plus it has floss pads on every floor that I regularly replace.
I am very surprised that you say I should actually have lights on for longer. Everyone on FB Aquascaping pushed me to reduce the lights, I actually started on 7.5 hours. Could you please explain why? I thought that the last solution with algae is to do a total blackout. Do you think I should just go back to 8 hours a day? Being honest my 5 hours apparently isn't working anyway so I can give it a try. I checked the posts mentioned and the first one says his problems were sorted by adding a skimmer. I would say my flow rate is pretty good (even when feeding the food immediately scatters everywhere around) but truth to be told, I have an oily film on the surface that I regularly remove and have no idea where it is coming from. Can it actually be it?


----------



## dw1305 (3 Feb 2021)

Hi all,


HoneyGourami said:


> I am very surprised that you say I should actually have lights on for longer. ............ Could you please explain why?


I've always <"run my tanks on a 12 hour day"> the original rationale was that that is how long the day is on the equator. <"Cristel Kasselmann"> likes <"a 12 hour day as well">.

I'm not a CO2 user, so others will have to explain why a short photoperiod may be more appropriate for a CO2 injected tank.


HoneyGourami said:


> Plus it has floss pads on every floor that I regularly replace.


Personally I'm <"too lazy to use floss">, I don't actually like any mechanical filtration inside the filter. Have a look at <"New Filter........">.


HoneyGourami said:


> I have an oily film on the surface that I regularly remove and have no idea where it is coming from. Can it actually be it?


It may be <"from the food">. A skimmer will definitely work for the surface scum. We have <"quite a lot of posts about them">.

cheers Darrel


----------



## Jaseon (4 Feb 2021)

Strange isn't it? You could most probably set up the tank again the exact same way, and not have this problem. Ive heard of people being recommended to black out the tank for several days for algae issues which kinda fly in the face of having a longer photoperiod. How long has the tank been up, and running? Might be just a question of time as the tank continues to mature?


----------



## dw1305 (4 Feb 2021)

Hi all,


Jaceree said:


> Ive heard of people being recommended to black out the tank for several days for algae issues which kinda fly in the face of having a longer photoperiod.


I'm not a great "black  out" fan either, really for much the same reason. I think there might be a use for them where you've had an incident (dead fish perhaps) that has caused BGA etc. Then you could have a black out, syphon out the debris and hopefully it's problem over.

In other circumstances may give you a reset in the short term, but in the longer term you've not addressed whatever your problem was and you may have compromised plant growth.

I think of black outs, algicides (in fact <"all magic bullets">) as a bit like <"dosing yourself with antibiotics"> every time you are ill, it may work some of the time, but in the longer term you are destroying your gut biome and compromising your future health.

Plant growth is what I'm interested in, not necessarily optimal plant growth, but <"plants in active growth">, and a large biomass of them. 

cheers Darrel


----------



## Jaseon (4 Feb 2021)

dw1305 said:


> Hi all,
> 
> I'm not a great "black  out" fan either, really for much the same reason. I think there might be a use for them where you've had an incident (dead fish perhaps) that has caused BGA etc. Then you could have a black out, syphon out the debris and hopefully it's problem over.
> 
> ...



Yeah i did read that the plants can go without that light but the algae cant. I mean over say several days. Either way its not something id like to try or do myself. I did search for how long can plants in general survive a blackout period. Id assume plants that are not actively growing would fare better etc. Was reading succulents can go without light for up to 14 days without any ill effect so depends on the species?.


----------



## dw1305 (4 Feb 2021)

Hi all, 


Jaceree said:


> Was reading succulents can go without light for up to 14 days without any ill effect so depends on the species?.


Yes, very species dependent. Some plants are adapted to low light conditions, if you think of Ivy (_Hedera helix_) on a woodland floor, it might have weeks in the winter when they don't reach light compensation point (LCP) and you could have even darker conditions on the arctic tundra, or under a snow bank, where low light levels might extend for more than six months.

Against that you will get plenty of <"turned up to eleven"> plants near the equator, which need their <"light fix every day">. 

cheers Darrel


----------



## HoneyGourami (6 Jul 2021)

Hello, I wanted to give an update in case anyone has the same problem, what finally helped me was Phosguard. After around 2 weeks of use, FD disappeared and never came back.


----------



## dw1305 (6 Jul 2021)

Hi all,


HoneyGourami said:


> what finally helped me was Phosguard. After around 2 weeks of use, FD disappeared and never came back.


If you still have the Phosguard in? It isn't a solution in the long run and you will definitely eventually have problems. Phosphate (PO4---) is one of the three macro-nutrients that plants need most of, but it is <"highly mobile in the plant">, so they can shuffle it from old to new tissue, but it  will eventually run out.

Algae can't do this, they don't have any internal plumbing, so deficiency symptoms appear a lot sooner.

cheers Darrel


----------



## HoneyGourami (6 Jul 2021)

dw1305 said:


> Hi all,
> 
> If you still have the Phosguard in? It isn't a solution in the long run and you will definitely eventually have problems. Phosphate (PO4---) is one of the three macro-nutrients that plants need most of, but it is <"highly mobile in the plant">, so they can shuffle it from old to new tissue, but it  will eventually run out.
> 
> ...


no I did it for 2 weeks a few months ago, it immediately helped, and then it was not needed (FD never came back after that). I only posted as it might help someone else in the future


----------

