Cyanobacteria.

BigBen1989

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Hey guys.

I've moved house recently and one of my tanks has ended up in a fish in cycle (I hate this method under normal circumstances). I've lost a number of discus during and after the move, but I'm pretty much there with the cycle.

The bit that I don't know how to deal with is Cyanobacteria on the substrate. I've been cleaning it daily but in 24 hours I get another patch coming up, very frustrating. Any suggestions?

I also have diatoms as well, but I know they'll disappear in a month or so.
It's currently a bare tank with sand substrate, with 3 discus and some lemon tetras.
pH is about 6.8
Ammonia - 0ppm
Nitrites - 0.25ppm (pre water change)
Nitrates - 40ppm

My other tank moved fine from a chemistry point of view, but lost some Cory's in transit.

Many thanks,
Ben.
 

Colin_T

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You need to reduce the nutrients in the tank but it could be difficult considering you are in the UK, which regularly has high nitrates.

Maybe look into a reverse osmosis unit for water with less or no nitrates.

Floating plants can help reduce nitrates and reduce light getting to the bottom, thus removing 2 sources of food for the Cyanobacteria.

Cut back on dry food and use frozen or live.

Increase water movement and aeration, especially around the bottom where the Cyanobacteria is.

If you have old fluorescent lights (more than 12 months old), replace the globes with new globes that have a 6500K (K is for Kelvin) rating.

Just keep trying to remove it physically.
 

Oblio

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If you can reduce the light intensity and duration, that has helped me, especially the intensity part.
 

Lynnzer

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Cyanobacteria is dependant on light to multiply. Give it a go with blacking out your tank completely for a couple of days at a time then manually remove any when you open the tank up again. Repeat as necessary every few days after the fish recover. The fish will manage this fine for a couple of days, even if they aren't fed.
A UV filter will kill any bacteria that passes through it, which will prevent the spread of it.
There are also fish safe chemicals that you can use.
 
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BigBen1989

BigBen1989

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Thanks. The tap water here doesn't really show much through the API kit, so less than 10ppm. It's at 40ppm in the tank because of the cycle. I've had higher readings on ammonia and Nitrite today, so it's not as nearly there as I thought.

I have a controllable LED light unit that I can adjust so I'll start reducing it.

I'm due to fly to New York for a week on Saturday. The tank will be covered when I get home and with it cycling I'm concerned that what I have left will be lost.

Does easy carbo have any effect on Cyano?
 
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BigBen1989

BigBen1989

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no idea what easy carbo is???
It's a product by easylife, sold as a "liquid co2". I'd seen in the past that if injected upon algae it kills it, however it appears that it's hair algae it kills.

If it worked it would only have been a temporary fix until I can sort out my water issues.
 

Essjay

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The tap water here doesn't really show much through the API kit, so less than 10ppm. It's at 40ppm in the tank because of the cycle.
You said in post #1 that you are doing a fish-in cycle. Since this involves very frequent, if not daily, water changes, the tank water should be very similar to your tap water. Where tap water has low nitrate, tank nitrate should never get that high.

How often are you doing water changes?
 
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BigBen1989

BigBen1989

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You said in post #1 that you are doing a fish-in cycle. Since this involves very frequent, if not daily, water changes, the tank water should be very similar to your tap water. Where tap water has low nitrate, tank nitrate should never get that high.

How often are you doing water changes?
I was daily. I'd stopped as I thought the cycle was done, but seemingly not as ammonia and Nitrite are high again. I'd do daily again now, but I'm heading to America tomorrow. My WC's have been around the 50% mark.

From lots of fishless cycles (my preferred method!), I don't think the nitrates going up to this level is that unusual?
 

Lynnzer

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If it worked it would only have been a temporary fix until I can sort out my water issues.
Yeah. I have that problem too. I put it down to age or way too many cups of coffee each day
 

Essjay

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Fishless cycles do get a lot of nitrate. All that added ammonia is converted into nitrate and water changes are not done until the cycle has finished so nitrate can get quite high.
With fish-in cycles, water changes should be done whenever ammonia or nitrite are above zero, and these frequent water changes keep nitrate at or just above tap level.


Nitrate should be kept below 20 ppm as high than that is harmful for fish. When tap nitrate is 10 ppm or below, it should be easy to keep the tank level below 20.
If tank nitrate is well above tap level, the usual causes are one or more of - too many fish; overfeeding the fish; not frequent enough or large enough water changes; not cleaning the substrate; not cleaning the filter.
 

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The fastest way is to dose your tank with antibiotics. Next way is hydrogen peroxide- but be very careful as that can be toxic to fish in either fast or slow manner. Another way is remove by hand and and clean your filter 2-3x a week. The prefilter,not the bio filter. Also,it will grow below your substrate facing the glass panels- so stir that up when you remove the BGA.
Really,big water changes never do much for BGA. In fact DON'T change the water and clean your filter will do more to keep it in check.
Last option is remove manually all the BGA you can and add a UV filter that will kill floating spores of BGA..so as you remove all you can see,it should die off by attrition.
 

I Like Rare Fish

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From experience:

I got a NANO+ water sterilizer, which worked very quickly and succeeded. However, you can turn off lights and only have on for 2-3 hours a day, and add floating plants such as Duckweed or Mosquitofern to attempt to compete with algae. Suck it off the bottom substrate to get rid of some of it. If it spreads to the sides I would scrape off and the next day use a gravel vac to suck it up.
 

Stan510

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Go dark is the simplest way- but if you have plants that are sizable,you might have a problem. If you don't have plants- leave the lights off and if it's getting light from any windows- you should just put a tarp over the aquarium for a few days.
But will still need to lower the nutrient load- that's what that algae feeds on also. Good gravel and pre filter cleaning will work.
 

Lynnzer

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Fishless cycles do get a lot of nitrate. All that added ammonia is converted into nitrate and water changes are not done until the cycle has finished so nitrate can get quite high.
So, logic dictates that a fishless cycling period must allow ammonia to be present otherwise it really doesn't get going at all? In which case I suspect that frequent water changes will only reduce the ammonia level thus slow everything down?
 

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