Any thoughts on UV treatment?

[Sanniejop]

Hi,
I am now for two months in the process of starting up a new aquarium. Most goes well plants are growing but my water keeps having a green tint. I suspect it is al low concentration of green water algea. Algea that is lose in the water.
Now i read that an UV lamp will solve this very effective but i was wondering what the general opinion is here at UKAPS about this type of devices?
I try to replicate the same conditions as in my older smaller tank which has always very clear water without the use of any fancy stuff. Just only a filter. So i am thinking it should also be possible with my new tank. But it keeps looking greenish.

Thanks for your advice

 

[hypnogogia]

Thread 'Please read the guidelines for Algae help!'

27 Apr 2020

Dear Member

Please give as many details as possible regarding your aquarium set-up, when requiring advice/help!

The above will be posted at the start of each help request.
Why do we ask these questions?
It will stop the member posting multiple times, plus adviser's don't need to scroll through a whole thread to find them.

Copy and Paste the list below...and add your answers to each number on the list!
Please upload photographs/images if possible.

1. Size of tank in litres.
2. Age of the set - up.
3. Filtration + Media/Sponges.
4. Lighting and duration.
5. Substrate.
6. Co2 dosing or...

• G H Nelson

• 

 

[Sanniejop]

Movie of the problem.


1. Size of tank in litres.
Approximately 410L netto including filter

2. Age of the set - up.
Started januari 1st 2025

3. Filtration + Media/Sponges.
Eheim 5e700 running on 644L/h according the filter ifself.
Using the standard foams and further completely filled with Sera siporax
Currently using purigen for removing tannis from wood.

4. Lighting and duration.
Giesemann Pulzar 3g
5.5 hrs on 100%, 11.5 hrs 50% or higher, see light profile

5. Substrate.
plain gravel and some aeea with sand

6. Co2 dosing or Non-dosing.
Co2 dosing yes. Played with different settings. Steering around ph 6.8 measured with pen. Currently using 24hrs co2 (just like my other tank that looks cristal clear) using a separate pomp circuit with reactor.

7. Fertilizers used & Ratios.
Was using pps pro just like in mg other tank. Now lowering the dosage because of the relatively higer fish load compared to my other tank and the use of some crypto grow caps in substrate on some places.

8. Water change regime and type.
When tds touches 200 i do a 140 liter water change 100 liter rain water plus 40 liter tap. Resulting KH 3. Add some extra epsom for ratio Ca:Mg 2:1. These ratios worked always very wel in my other tank.

9. Plant list + When planted.
Most plants are planted over from my other tank.
At startup lots of :
elodea densa
Hygrophila polysperma
rotalas
Duck weed
crypts

Later added/
Anubias
Tiger lotus (baby)
Hemianthus of Micranthemum callitricoides "Cuba"
Alternanthera reineckii
Alternanthera mini
Lysimachia Nummularia aurea
Eleocharis acicularis
Bacopa monnieri
Rotala Wallichii
Bucephalandra Brownie Ghost
Java Trident

10. Drop Checker.
Light green

11. Inhabitants.
12 Congo tetras
14 corydoras julii
14 diamont tetra
3 zebra loach
1 siamese algea eter
2 otocinclus
5 amano shrimp

12. Full tank image & Surface image.
Some quick pictures at day light. Also after trimming yesterday. One picture before trimming.
Detail it is a look through aquarium in a quite bright room. But my other aquarium is right next to it doing fine, see pictures.

Any help appriciated. Thanks in advance.

 

[Little]

Sunlight will cause green water, UV will kill it.
Seems a simple fix if you have water that gets a lot of sunlight.

I use UV in my ponds. Changing bulbs yearly is a bit of a pain but it’s not too bad.

I used to set timers so the bulbs only ran 12 hours per 24 but I was told the bulbs last just as long when running 24/7 and the energy use is pretty minor (I have solar panels anyway).

 

[Sanniejop]

Funny thing is sunlight is also containing UV.
I have also a pond, never used UV or even any filter on it. Alway cristal clear water.

Inside the house the UV is removed from the sun light by not passing through the window glass.
So i can imagine that only the high light intensity of some sunlight might cause the algea. But there is only a limiting amount of direct sunlight into the tank. Its only less than 1/2 an hour. Same counts for my other tank, no problem there.
One difference between my tanks is that my old one uses two T5 bulbs on for 11 hours per day.
My new one uses "one" very strong led light. On for 5.5 hours on 100%.
But i was wondering if the localy very strong light could cause the algea growth. Simply Lowering the light intensity causes bad growth for normal plants further located away from the led bar.
Solution could maybe be adding a second led bar and use them both on half the power. Limiting the intensity ghat is maybe causing the algea.

I have now reduced the time on low intensity to see if this has an effect.

UV treatment seems simple but has it any other disadvantages next to power use?

 

[dw1305]

Hi all,

Approximately 410L netto including filter

Most goes well plants are growing but my water keeps having a green tint. I suspect it is al low concentration of green water algea. Algea that is lose in the water.

I wonder if it is just the internal reflections from the plants giving you a green tint? Particularly as it is such a big tank

Using the standard foams and further completely filled with Sera siporax
Currently using purigen for removing tannis from wood.

Are the sponges green when you clean them? That should filter out any phytoplankton.

cheers Darrel

 

[Connswater]

sunlight is also containing UV

Yes, and direct sunlight is sterilising, laundry on the line. In a motor car polaroid sunglasses do not go dark because the car windows block the UV. I used UV on my goldfish pond, it clears Spring green water within a week and keeps it gone throughout the growing season. My tanks do not get green water, but on my main tank I use UV to protect my black mollies in water a little softer than is ideal for them, UV is the best preventative measure I have found against white spot. If your tank is getting green water from excess sunlight but is otherwise going well, and it looks very good to me, I would expect UV to eliminate the problem.

 

[hypnogogia]

Movie of the problem.

Can’t access the movie. Photos of tank don’t seem to show the problem.

 

[hypnogogia]

I wonder if it is just the internal reflections from the plants giving you a green tint? Particularly as it is such a big tank

I was wondering that too, especially if the glass isn’t low iron.

 

[simon_the_plant_nerd]

Is the water green when you take it out to do a water change? I never used to have green water in my tank. Changed the substrate, now I do. It’s definitively green as it’s green in my white water change bucket.

It doesn’t bother me enough to buy a UV but it’s definitely some sort of algae.

 

[Maf 2500]

If it looks like pea soup, get a UV. If it doesn't, don't bother. I would rather have a very slight (and hard to see) green tint from phytoplankton than most other types of algae.

If the filter is only turning over 644 L/h on a 410 litre tank I would think about adding another filter before I went down the UV route.

 

[hypnogogia]

If the filter is only turning over 644 L/h on a 410 litre tank

That’s very low for a high tech tank (unless there is another flow pump in there somewhere)

 

[Sanniejop]

Hi all,


I wonder if it is just the internal reflections from the plants giving you a green tint? Particularly as it is such a big tank

Are the sponges green when you clean them? That should filter out any phytoplankton.

cheers Darrel

Difficult to judge. There is only one white sponge in it and the filter was run in on the small aquarium. I only cleaned it once just shortly ago and then it was brown.

 

[Sanniejop]

Can’t access the movie. Photos of tank don’t seem to show the problem.

The latest picture shows the particles.
Can nobody see the movie ???

 

[Sanniejop]

I was wondering that too, especially if the glass isn’t low iron.

It is low iron glass. I just did not choose for the transparent kit. You still see the edges and than i like black more also because if it gets dirty. But it is low iron Thats the reason why i am really not happy with this. This way i could left out the investment of using low iron. Because it is s look trough tank i wanted low iron

 

[Sanniejop]

Is the water green when you take it out to do a water change? I never used to have green water in my tank. Changed the substrate, now I do. It’s definitively green as it’s green in my white water change bucket.

It doesn’t bother me enough to buy a UV but it’s definitely some sort of algae.

Yes? Cant show you picture now. I am on a vacstion for a few days now.

 

[Sanniejop]

If it looks like pea soup, get a UV. If it doesn't, don't bother. I would rather have a very slight (and hard to see) green tint from phytoplankton than most other types of algae.

If the filter is only turning over 644 L/h on a 410 litre tank I would think about adding another filter before I went down the UV route.

I can crank the filter speed up a bit (on its max it gives a bit more than 900 l/h). But than i have to increase also the co2 bps since the surface agitation will also increase. It seemed i could tune the ph level with the speed/surface agitation of the filter. So now it is not on the max speed. There is another 600 l/h pump connected to the co2 reactor giving some extra circulation. I am planning to replace that pump with the filter from my small aquarium so i will have extra filter capacity.
For some reason i have the feeling the 5e does not take out the particles very efficiently. It has only one blue sponge and one white fleece. That doesn,t seem much to me isn't it??? Thats also one reason why i put the glow down, because of the idea that if the flowc inside the filter is to strong it just presses the particle through without beeing catched by the sponges. Dont know if that makes sence???
Also the possibility to variate the speed i stopped using (high speed over night low at day time) brcause i though this could make particles trapped in the filter to come lose again. So i choose to use a constant speed now.

 

[Sanniejop]

Can’t access the movie. Photos of tank don’t seem to show the problem.

It should work now, let me know please....

 

[PARAGUAY]

Your plants look very healthy off the photos, try reducing light intensity with few small water changes

 

[hypnogogia]

It should work now, let me know please....

Yes, working and I can indeed see the tiny little green bits in suspension. My advice is add filtration as already suggested. for a 400L tank, you need a big filter like an FX6.