[Dzonik]

Hello planted tank experts,

I’ve never had long term algae issues, but since I moved to different location and set up my new tank I am constantly fighting thread / hair algae. The aquarium is running for 6 months and I am desperate already - first I was doing lean fertilization with Tropica Specialized and for the past 2 months I am doing EI – the plants are visibly healthier and bigger, but no change to algae. I am cleaning the tank thoroughly every week (along with 50% water change). If I skip one week, the algae grows on everything, there are even long threads growing from otherwise healthy plants.

Interestingly, the plants look perfectly healthy, but they never pearl (even if I crank up the light to 100%) and they grow slower compared to my previous place aquarium where I used to have massive pearling with less ideal conditions.

I tried all advices I could find with no significant improvement… any help would be greatly appreciated 😊

Aquarium specs:

• tank size: 30 gallons
• substrate: ADA Aqua Soil Amazonia Ver. II
• filter: Oase Biomaster 350 + Seachem matrix
• light: Twinstar 900EA - 6 hrs at 70% + another 5 hrs at 5% (I have to keep the light at 70% at most, otherwise the algae takes over completely)
• CO2: pressurized, 1.5 bubbles per second, turns on 3 hrs before light, turns off after 6 hrs of intensive light… drop checker is constantly yellow-green
• fertilizing: EI (Tropica Premium for micros)
• fish: 10x caridina japonica, 15x tetras, 4x otocinclus, 10x cherry shrimps
• last measured water parameters (lab tested, right before water change):
  • ph 6,88
  • 12.62 dGH
  • 6.5 dKH
  • Fe 0.22 ppm
  • NO3 38.8 ppm
  • K 38.1 ppm
  • PO4 0.02 ppm
  • CA 40 ppm
  • Mg 7 ppm
  • NO2 0.013 ppm
  • NH3 0.02 ppm

Here is couple pictures showing plants' health and algae infestation:

 

[ytro]

.02 ppm po4 is pretty close to zero, which concerns me. I would increase it and try reducing no3 a little bit. Maybe shoot for more like 2ppm po4 and 20ppm no3 (1:10 po4 to no3 ratio is a good balance). I would also look to reduce the lighting intensity to maybe 50-60% until the algae calms down some. Also, not sure for the 5hrs at 5%, but I would eliminate that as well. Keep up with the weekly water changes and manually remove as much algae as possible. Give it a couple weeks and see what happens...

 

[Plinkploop]

Could it be possible that where you moved the tank to has more ambient light? I agree with the past comment on ferts but I'm just curious because I've often had hair algae issues due to ambient lighting. * edited for spelling

 

[Dzonik]

I am currently adding 6 ppm of PO4 per week in two doses... I noticed it is almost unmeasurable after 2-3 days. Should I really go even higher?

Also, I am keeping 5% light for the viewing purposes during afternoon / evening.

Regarding ambient light, there is much more now - two big windows on both sides (though almost no direct sunlight on the tank). Is there anything I can do about it except moving the tank / making the room darker? I am afraid if I lower the light even more, my plants will never pearl again (which is not a problem probably). Should I target my main photoperiod to mid day or rather early in the morning in this case?

 

[Plinkploop]

I'd say get some curtains and close them during the day, there are probably ways to tweaks your ferts and actual lights to help a little, but I'll bet dollars to doughnuts it's the ambient light throwing you off. I used curtains and blinds and it worked great, but large windows are a whole different scenario. I wish I cold give you an answer other than move the tank but if you can't block out the light it is the easiest method least experimental ways to handle it.

 

[Tiger15]

There are different type of thread algae. The soft type, commonly called hair algae, are eagerly eaten by Amano shrimp, SAE and Molly. The hard type, silky spirogyra or the branching Clado are untouched by any algae eater. Do you know what you have?

 

[Asteroid]

To me, more than likely a lighting issue based on what you have going. Your dosing the water column and your using ADA AS, very unlikely it's a fert issue after 6 months.

What was the lighting cycle when you started the tank? What is your approx. PAR? What was your water change schedule at startup?

 

[jellopuddinpop]

I am currently adding 6 ppm of PO4 per week in two doses... I noticed it is almost unmeasurable after 2-3 days. Should I really go even higher?

Also, I am keeping 5% light for the viewing purposes during afternoon / evening.

Regarding ambient light, there is much more now - two big windows on both sides (though almost no direct sunlight on the tank). Is there anything I can do about it except moving the tank / making the room darker? I am afraid if I lower the light even more, my plants will never pearl again (which is not a problem probably). Should I target my main photoperiod to mid day or rather early in the morning in this case?

ADA Aquasoil will absorb PO4 from the water column. I would increase PO4 dosing in the short term, and watch closely. Eventually, the substrate will stop absorbing PO4 and you’re going to want to cut back significantly.

As for keeping your lights high to induce pearling, I wouldn’t count on that. Pearling is not exactly a sign of a healthy plant. For all you know, the algae is pearling just as much as the plants are =). I would get the algae under control (some very good ideas already given), then worry about pearling once the plants are strong and healthy.

 

[Plinkploop]

My algae pearls beautifully

 

[Asteroid]

ADA will absorb some po4, but it's still available to the plants. The entire ADA system is based on that. I've done around 10 ADA AS-based tanks and never added po4 to the water column in the first year. Plants actually look pretty healthy they just can't deal with algae from lighting imbalance.

 

[Dzonik]

This is the soft type thread.

I don't know the PAR, but it is 52W /3950 lumens LED light. I did dark start for the first month - completely covered. The lights are on for 6 hrs (70%) + 5 hrs (5%) since beginning. I am changing 50% water also since beginning.

The idea with ambient light makes a lot of sense to me, but is a big problem for my setup - the room is full of house plants taking priority. For the start, I will lower my lights by another 20% and increase my PO4 dosing temporarily. Do you really think I shouldn't keep those 5% for another couple hours? Maybe just 1% or nothing?

 

[Asteroid]

This is the soft type thread.

I don't know the PAR, but it is 52W /3950 lumens LED light. I did dark start for the first month - completely covered. The lights are on for 6 hrs (70%) + 5 hrs (5%) since beginning. I am changing 50% water also since beginning.

The idea with ambient light makes a lot of sense to me, but is a big problem for my setup - the room is full of house plants taking priority. For the start, I will lower my lights by another 20% and increase my PO4 dosing temporarily. Do you really think I shouldn't keep those 5% for another couple hours? Maybe just 1% or nothing?

How big is the tank? Also the ADA substrate really requires daily water changes 1st week, every other day 2nd week until you get to the once a week. If you didn't do that and running high light for 6 hrs at start that's a difficult combo to avoid algae.

 

[Dzonik]

Tank size is 30 gallons, 15 inches height. I didn't know I should do the water changes so often... now I am thinking to change to twice a week for some time, thought too late probably.

Also, about the lack of pearling - this was the reason I was thinking I am missing something (instead of having some excess). Can you have a healthy high light / rich CO2 tank without plants pearling?

 

[jellopuddinpop]

Can you have a healthy high light / rich CO2 tank without plants pearling?

Yes, absolutely. The plants will only pearl if the water is completely saturated with O2, and can't hold any more in dissolved form.

 

[rzn7z7]

• light: Twinstar 900EA - 6 hrs at 70% + another 5 hrs at 5% (I have to keep the light at 70% at most, otherwise the algae takes over completely)
• CO2: pressurized, 1.5 bubbles per second, turns on 3 hrs before light, turns off after 6 hrs of intensive light… drop checker is constantly yellow-green

I'm guessing you're CO2 limited - 1.5 bps may have been adequate initially but with increased plant mass you need more CO2

I'd ditch counting bubbles and the drop checker and go with a simple ph pen, something like this

You're looking for at least a 1.0 ph drop thru the course of the day....once you get CO2 dialed in you'll probably find yourself limited by some other macro like N, P, K, Ca or Mg...but start with CO2

Lastly, IMO this is recommended reading for those with algae issues

Green Aqua algae guide

 

[Asteroid]

Tank size is 30 gallons, 15 inches height. I didn't know I should do the water changes so often... now I am thinking to change to twice a week for some time, thought too late probably.

Also, about the lack of pearling - this was the reason I was thinking I am missing something (instead of having some excess). Can you have a healthy high light / rich CO2 tank without plants pearling?

Sounds like a good amount of light, but I'm not sure. I usually start off tanks with a 3 hr strong intensity and the rest dimmer. Coupled with the water changes, good co2 and the use of carbon in the filter. The co2 increases uptake of organic decomposition which contains ammonia and usually the catalyst in most if not all alga. The carbon will help remove organics before they decompose. The more plants you have the more uptake and the easier it is to avoid issues. It's not too late to do these things. It should help.

There are two types of pearling. When a tank is saturated with o2, pretty much everything pearls, even algae. This is really "fake" pearling. True pearling has to do with how fast a plant is photosynthesizing and releasing o2. You could have a single stem (no other plants in the tank) and it will pearl, because the o2 is being released too fast to be absorbed into the water. Similar to the way if you cut a stem in a "pearl-less" tank, you see the stream of o2 coming out of the cut stem. It's not being held back by anything and can't be absorbed quick enough. You don't need pearling to have a healthy tank, but it's kind a hard for algae to stick to a bubble if you know what I mean.

 

[Dzonik]

Ok, so you confirmed my suspicion that the plants may be lacking something because they do not grow fast enough to pearl. If it's not light / nutrients, only CO2 remains...

I'm guessing you're CO2 limited - 1.5 bps may have been adequate initially but with increased plant mass you need more CO2

I'd ditch counting bubbles and the drop checker and go with a simple ph pen, something like this

You're looking for at least a 1.0 ph drop thru the course of the day....once you get CO2 dialed in you'll probably find yourself limited by some other macro like N, P, K, Ca or Mg...but start with CO2

I am using also the kind of CO2 test where you add the drops one by one to a vial with testing water until the color changes - this test shows around 30ppm. That's why I didn't suspect CO2 to be low. Can you tell me more about this ph pen method? I just measure the ph at the beginning and end of the photoperiod and add the CO2 until the difference is at least 1 ph?

I am worried if I add CO2 beyond yellow drop checker, I might hurt the fish.

 

[Asteroid]

Ok, so you confirmed my suspicion that the plants may be lacking something because they do not grow fast enough to pearl. If it's not light / nutrients, only CO2 remains...



I am using also the kind of CO2 test where you add the drops one by one to a vial with testing water until the color changes - this test shows around 30ppm. That's why I didn't suspect CO2 to be low. Can you tell me more about this ph pen method? I just measure the ph at the beginning and end of the photoperiod and add the CO2 until the difference is at least 1 ph?

I am worried if I add CO2 beyond yellow drop checker, I might hurt the fish.

No co2 measurement method is perfect, but as @rzn7z7 mentioned, normally a 1.0 drop would indicate good co2. You want the difference between degassed and fully gas co2. So I would take some water from your tank shake it up and set it aside for several hours maybe the day. Measure the difference in the PH in the water you set aside (degassed) and the water in your tank at peak co2, usually a few hours after it's running. The co2 enriched water should have a ph around 1.0 lower than the degassed water you set aside. You don't need a ph pen to do this, but it does make it easier to interpret than from a color chart in a test kit.

 

[jellopuddinpop]

To expand and clarify, here's the "For Dummies" version...

CO2 injection will predictably reduce the ph in your tank. If you know what your "degassed" ph is, then you can use that number to figure out how much CO2 is in the water when you're injecting it.

To get a degassed sample, take some tank water and leave it out for a good, long while (like a full day or two). Check the ph, and write it down.

Then, on a weekend or sometime when you're around all day, check your tank ph right when your lights come on. You want that ph to be at least a full point lower than your degassed water.

The tricky part is tweaking a combination of CO2 injection with surface agitation. Too much surface agitation, and you'll never achieve a 1 point drop. Too little, and your CO2 will continue to climb during the day, and put your livestock at risk by the end of the photo period.

Here is an excellent article to explain surface agitation in greater detail...

Surface agitation & gaseous exchange in CO2 injected tanks

Surface agitation in a planted aquarium - yes or not ? This page explores why having some surface agitation and turnover is actually useful in planted tanks and actually makes tuning CO2 to optimal levels more easy.

www.2hraquarist.com

You can also click the link in my signature to check out my journal. You can see how I monitor my CO2 to give you some ideas.

 

[rzn7z7]

I am worried if I add CO2 beyond yellow drop checker, I might hurt the fish.

Based on experience a 1.0 pH drop should not bother the fish but, yes, watch the fish as you increase CO2 for any signs of stress, such as heavy breathing, lethargic behavior, swimming near the surface, etc. If you see any of those signs then turn off the CO2, turn on air stones, open hood/canopy tops, point filter returns to the surface to increase surface agitation....anything to help dispel the CO2 and increase oxygenation