[KOKORO]

Tank: approx 150G (4’x 2’x 3’)

Water Parameters:
Ammonia = 0
Nitrites = 0
Nitrates = >5
PH = 7.9
GH = 9 drops
KH = 8 drops
(Don’t have a kit for phosphates yet)

Stocking: 6 x juvenile Julidochromis Dickfeldi (approx 2 inches) and 1 x 3 inch BN Pleco

Feeding: I feed NLS Grow pellets once or twice a day, about as much as they can eat in 30 seconds. Sometimes when I am not home my partner feeds them so I suppose it is possible he is overfeeding but if this were the case wouldn’t the Nitrates be higher?

Filtration: Ehiem Pro 3 2075 and Eheim Classic 2217 plus AC 110. I also have a Hydor Koralia 4 in there for extra circulation.

Water changes: I do a 33% to 50% water change once per fortnight (the tank is very understocked at the moment so the nitrates really don’t get any higher than 10ppm even after 2 weeks without a water change).

Substrate: Aragonite sand

Lighting: 4 x Hagen Glo T5 bulbs:
1 x Life Go
2 x Power Glo
1 x Marine Glo

The lights are on automatic timers from 6am – 9am and then again from 4pm – 9pm so the lights are off when I’m not home to view the tank. The tank gets no direct sunlight but may get some indirect sunlight during the late afternoon as it is facing windows.

Plants: Lightly planted with about 20 vallisneria – both giant and corkscrew and 2 small/medium anubias attached to small pieces of driftwood.

Originally I was using 1 Life Glo bulb and 1 Marine Glo and found I was getting brown algae on the rocks and glass and the vals weren’t doing so well.

I swapped out the Marine Glo for a Power Glo to try to turn the algae green but I found the light too yellow and the fish colours didn’t pop like they did under the blue light. So I bought a second light fitting and added back in the Marine Glo plus a second Power Glo bulb.

I also added the BN Pleco at this point who does a great job at keeping the glass algae free.

I use Excel fertiliser about once a fortnight when I do a water change (2 cap fulls in 150G). I have also used some substrate tablets in the past but not for a few weeks now.

The brown algae is now gone and has been replaced by a dark green soft looking hairy type algae on the rocks that is about 2 cm long, the pleco eats some of this occasionally. I also had some very dark green patches of algae on the sand and one very bright green patch which I removed in the last water change (a 50%) when I vacuumed and stirred the substrate. I also cleaned out the Pro 3 and the AC110 with tank water.

The water change was done 4 days ago and I have noticed that since then the water has been gradually turning cloudy and has a definite green tinge. I am assuming that the cleaning of the tank and vacuuming and stirring the substrate has made algae spores water borne and this has led to a bloom.

I know I can blackout the tank for a few days and do some water changes to remove the algae but how do I stop a reoccurrence of this problem? Do I need to reduce lighting intensity or duration, increase CO2 , reduce phosphates or all of the above?

Hoping a planted tank guru out there can point me in the right direction before I start experimenting!

Sorry for the long post! Hopefully you are not :zz:

 

[DJRansome]

I had the same problem as you a while back. I solved THAT problem so hopefully my solution can help you. I am still struggling for balance but things are better!

The green-bright green-blue green algae especially on the substrate may be cyanobacteria.

I also had vallisneria planted (contortionist) in flourite pillows at the time.

My nitrates went to zero due to the vallisneria which is a very fast growing plant.

It was explained to me that if the vallisneria growth outpaces the nitrate available it will suffer and leak plant material into the water. This is the food for cyanobacteria.

The solution I was given was to plant more vallisneria and add nitrate via fertilizer.

I tried that but like you, could not achieve balance. The valls were either growing out of the tank and flowering or languishing.

I decided to try a not-so-fast-growing plant and removed the vallisneria, in spite of the fact that it is one of my lifelong favorites.

That worked for me. My tank is planted primarily with red rubin swords and I have some algae but no more cyanobacteria. Nitrates in the tank are no longer zero, even without fertilizer. I'm starting a program of Excel (carbon, not fertilizer), nitrogen and micronutrients along with root tabs to see if I can get rid of that last bit of algae.

There are members (fmueller, Fogelhund) who grow lush tanks without special substrate, lights or added fertilizer but I have not been able to achieve those results.

Hope this helps!

 

[hollyfish2000]

Personally, I've had trouble finding balance in lightly planted tanks (such as yours) in terms of algae. I've had much better luck planted the he$$ out of the tank, including some fast-growing plants, and adding C02 and fairly high light. I, too, like swords. I also like wisteria and giant hygro -- both grow fast and can easily be pulled out when they get "reedy." You can then trim them from the bottom and just stick back in the substrate. I love anubias, but I'm always seeming to battle BBA on the leaves since it grows so slowly.

 

[holjofish82]

I think the marine glow blub could be apart of the problem. How old are youre blubs ?

 

[KOKORO]

they are all new - less than 6 months. I have gotten rid of the green water after a blackout period of about 3 days and am now only using one of the light fixures with one power glo and one marine glo bulb.

This is working to reduce the algae but I think the vals are also suffering, they are looking a little pale although growth rate is still very fast and new runners are being put out.

I may have to try swapping the vals out for something slower growing as DJ suggested which is a shame because I really like the vals, they are great for a tank with extra height like mine.

**Edited to add**
My nitrates are zero even after 2 weeks with no water change, does this mean I should be dosing more ferts?

I am about to add 15 more fish (4cm cyps) this weekend if my order comes through as expected so I'm hoping that will help a bit by adding a bit more nitrates and more CO2 being produced

 

[DJRansome]

My nitrates are zero even after 2 weeks with no water change, does this mean I should be dosing more ferts?

Yes if you have plants and wish to avoid the dreaded cyanobacteria. Somewhere around 10ppm (no lower) is good.