Tank Algae Guru Needed!

[Lovegasoline]

I'm experiencing an attack of algae from hell and am nearing my wits end.

I have one male Red Eared Slider turtle about 12 years old with a approx. 6" shell, Mr. T. I adopted him when he was about 1 year old from a roommate who purchased him as a baby but was neglecting him due to ignorance on correct care... he lived in a salad bowl.
He's in a 37 gallon tank with a Rena/API Filstar XP2 large (3 basket) canister filter. He's fed in the tank with ZooMed Maintenance pellets, romaine lettuce, and occasionally with feeder fish, dried shrimp, carrot & other veggie bits. I have a foam filter over the water intake tube which is cleaned weekly to help keep the canister filter clean. The canister filter baskets contain: (bottom>top) #1) 4 foam filters from coarse to fine, #2) a full basket of Fluval Biomax ceramic media, #3) a single layer of filter floss.

The tank sits on the kitchen window facing north in NYC and gets direct sunlight part of the day. There's an above tank basking area. I realize the tank is a little small for the size of the turtle, however it's the only space available.

This tank setup has been stable for about 12 years, and has been doing well. The only change to the tank's filtration was that a few months ago I doubled the volume of the Biomax rings ... biomedia basket was always only half full since I set up the tank: I figured more media surface would offer better filtration so I ordered another box, effectively doubling the ring volume. In past years the tank would get algae only very occasionally, maybe once or twice a year and it's routinely eliminated by a thorough cleaning of the tank and filter along with 1-3 chemical treatments of Tetra Algae Control, then things are back to normal. Afterwards it might get a little algae formation on the glass, but the water remains clear after the cleaning and treatment.

However, for the past few months the tank water has turned completely green. I do 100% water changes and meticulously clean everything and treat the water with several applications of Tetra Algae Control, but the algae keeps returning with a vengeance in about a week or two, with the water turning avocado green or darker and you can't see more than a couple inches into the tank before any object is subsumed by the green murk.

What's different from the past instances of algae contamination is now the Fluval Biomax rings are completely indelibly green colored. They're stained green. In the past even on occasions that the tank turned green, the ceramic media would be an off-white-to-grayish color - not green. Now, they are green and after swishing and agitating them in tank water to clean them, they retain a heavy deep green stain ... the green tint has penetrated into the rings and will not wash off.

Anyway, a couple weeks ago I once again did a 100% tank water change. I meticulously stripped and cleaned EVERYTHING, every trace of algae from tank and filter. I removed hoses and scoured their insides as well as all fittings. I disassembled the filter inset sub assemblies and parts completely. The only thing I did not do is deep clean the Biomax rings, as usual I just swished them around in tank water so as to preserve the beneficial bacteria (I don't think rinsing them in tap water would even remove the green tint, it seems to have deeply penetrated completely through the material of the rings). I refilled the tank with tap water (NYC), added a little water conditioner, and also a treatment of Tetris Algae Control. About a week later the tank water is completely green. Gah! I'm at my wits end. This is becoming too much work. I'm not sure what to do at this point.

Could it be that the rings need to be either completely disinfected/cleaned and/or replaced entirely?

Anyone with advice or insight into why the tank is behaving differently now then previously, with water now perpetually green, and any suggestions on how to remedy this would be greatly appreciated. I never thought I'd get to a point where I'd consider giving my turtle away, but I share the place with roommates, the tank is unsightly, and because the water is nearly opaque green, it obscures half the sunlight entering the kitchen.

Help!

 

[brendenscott]

Too much light will feed the algae. Do you have live plants in there? If none then cut way back the light. Or if you added some that would also help against the algae. Remember algae needs light. The more you have the more algae you will get.

I would at least try to block some of that direct sunlight as 100% that's where it's coming from.

Until you get rid 100% of the green water algae to need to either use a UV sterilizer or 100 blackout for a few days.

 

[Lovegasoline]

Thanks for the reply.

The tank has been in the exact same position, with nothing added or taken away, for the last dozen years. The sunlight streaming into the kitchen window has been the same, seasonally dependent of course.

The last couple tank cleanings have been clinically fastidious ... every assembly and sub assembly disassembled and cleaned, every tube, hose, connector, nook and cranny ... cleaned and scrubbed. The only thing that wasn't defaulted to 'new' was the biomedia ... as mentioned they were unusually green ... a new development never before seen in this tank, even during the worst algae tank moments of years past. Should these be replaced with new?

I understand the algae needs light, but I have a hard time grasping how 'light' is the culprit when the degree of light has been constant (seasonally dependent) for the last 12 years. There's no more light now in NYC then in years past, nor more light in this window. But the tanks has been green for months despite 100% water changes and tear-down tank cleanings.

???

 

[mimiheart]

Second the UV sterilizer. Also, try 50% water changes rather than 100%. You're just resetting the cycle, or at least setting it back, even though more of the bacteria lives on surfaces rather than in the water itself.

 

[Lovegasoline]

OK, I'll try 50% H20 Change.

Are sterilizers expensive???
Dangerous for turtles?

 

[V227]

Obviously algae needs light to bloom, but it also needs nutrients. Since the tanks light exposure has been constant for the past 12 years with no algae problem, then maybe there has been an increase in nutrients to the water. The turtle might have grown just big enough to produce more waste than the bacteria can effectively handle.
Lovegasoline has certainly gone above and beyond in his effort to solve the problem. It seems to me that less exposure to sunlight and extra clean tank water is the likely answer.

 

[mimiheart]

OK, I'll try 50% H20 Change.

Are sterilizers expensive???
Dangerous for turtles?

Not dangerous at all. I use the Green Killing Machine 9v in my 40 gallon, it's about $50, $15 for replacement bulbs, but you don't need to run it continuously. If your turtle bites sponges there might be a problem with that one, as it does have a small sponge, but it works just fine in my 40 gallon that gets a LOT of direct light in southern California. (I even have a black background on the tank and have a black skirt in the window since I can't convince the landlord that curtains should be a thing combined with blinds.)

 

[Caliban07]

UV steriliser = problem solved [emoji846]

A floating plant like duckweed although quite invasive will soak up some of the excess nutrients and most likely provide a nutritious snack for Mr.T.

 

[Delapool]

Thanks for the reply.



The tank has been in the exact same position, with nothing added or taken away, for the last dozen years. The sunlight streaming into the kitchen window has been the same, seasonally dependent of course.




???

The only thing I can think of is adding the extra media may have slowed down water flow which then allows the algae a better chance.

Assuming nothing has changed on light coming into tank (windows cleaned, curtains?), I can't think of much else.

Any pattern to when tank got algae occasionally before? New feed, summer peak, filter flow dropping, etc, etc.

Interesting one. Cutting light / adding uv filter I'd do. Big cleans I've never found useful, the algae is always there, some nutrients will be there - it's preventing it from triggering (somehow lol).

 

[Lovegasoline]

Obviously algae needs light to bloom, but it also needs nutrients. Since the tanks light exposure has been constant for the past 12 years with no algae problem, then maybe there has been an increase in nutrients to the water. The turtle might have grown just big enough to produce more waste than the bacteria can effectively handle.
Lovegasoline has certainly gone above and beyond in his effort to solve the problem. It seems to me that less exposure to sunlight and extra clean tank water is the likely answer.

There's been algae bloom problems in the past, usually on the order of once or twice a year, during summer months. But cleaning the tank and treating with algae control chemicals once or twice (or three times at the very worst) would eliminate the bloom. With the bloom gone and especially during the summer season I'd still get some residual algae slime buildup on areas of the glass and filter tubing, but that's easily removed by wiping and I'd relegate that to standard tank maintenance & upkeep.
An algae bloom that makes the water a murky dense green and can't be eliminated, even with repeated cleaning & chemical treatments, is something entirely different and new.

 

[Lovegasoline]

Not dangerous at all. I use the Green Killing Machine 9v in my 40 gallon, it's about $50, $15 for replacement bulbs, but you don't need to run it continuously. If your turtle bites sponges there might be a problem with that one, as it does have a small sponge, but it works just fine in my 40 gallon that gets a LOT of direct light in southern California. (I even have a black background on the tank and have a black skirt in the window since I can't convince the landlord that curtains should be a thing combined with blinds.)

My turtle bites sponges and I don't place anything in the tank with him or he'll eat or otherwise destroy it (like plants, etc). He'd not only bite sponges but he'd knock off sections of the RENA/API/FILSTAR XP Filter intake tubing so I had to move to an array of the heavy duty magnetic suction cups to secure the tubing.

How critical is the sponge in the UV rig? Would it be a problem if the turtle decided he wanted to tear chunks of it off?

 

[brendenscott]

That's green algae for you. Many times cannot be eliminated without complete blackout or UV sterilizer. And as others mentioned now with higher nitrates and phosphates is making it harder to eliminate. You need to get to the source to eliminate it and that's light and nutrients i.e. Nitrates and phosphates. If you were to add some easy growing plants in there even some floaters those are great at keeping the nutrients in water under control which in turn makes it harder for the algae.

 

[brendenscott]

If no plants are an option then you should add a phosphate remover i.e. Phosguard or something similar. This would help starve the algae.

 

[Lovegasoline]

UV steriliser = problem solved [emoji846]

A floating plant like duckweed although quite invasive will soak up some of the excess nutrients and most likely provide a nutritious snack for Mr.T.

Thanks I'll look into introducing some duckweed although I have a feeling that Mr. T. will devour it all within the same day. As it he typically eats 1-2 large romaine lettuce leaves daily.

 

[brendenscott]

One more thing to keep in mind with that being a small size tank for the turtle means heavier bio load in the water. This makes it imperative for more water changes or I suspect the nitrates are pretty high. I recommend a 50% or more weekly water change to keep the nitrates lower. Remember algae needs very little nutrients and light to thrive. And one it gets going unless you get to the source it will keep coming back. It's very persistent.

 

[Lovegasoline]

Stop the presses!

The only thing I can think of is adding the extra media may have slowed down water flow which then allows the algae a better chance.

Hmmm. That's very possible.

Unfortunately my notes are not comprehensive so I'm not 100% certain when the bloom started: before I doubled the ceramic ring media volume, or after?
To recap the canister filter is a RENA/API Filstar XP2.


Here's my notes from March 26th:
"Mr. T's filter had been making a lot of gurgling noise. I disassembled the filter and the filter floss seemed uncharacteristically dirty [uppermost filter basket] , although the other 4 sponge filters were surprisingly pretty clean [note: they are typically very dirty, with the bottom/coarsest one extremely dirty]. I had 2 baskets of foam filter sponges (8 total)[Note: I've been using 8 filters for a long time], factory recommends only 4 (all in 1 basket). So, (x2)@30ppi, (x1) @20ppi, and a larger ppi non-OEM aftermarket sponge at very bottom the very bottom . Also, realize I should order more biomedia ceramics to double capacity. Next: buy replacement O-ring kit; if that doesn't improve noise issue I'll get a new impeller. Also clean the tubes."


Uhh, I'm not certain if I did a 50% or 100% water change at this time.

I now recall that there were changes to the filter setup!
I previously used 8 sponges, filling the lower two (of three) media baskets. The uppermost basket's bottom half was filled with Fluval Biomax ceramic rings, then the plastic screen separator, and the uppermost section of the basket had a single layer of filter floss. That's been my default setup for at least a year or two prior to doubling the ceramic rings.

I forgot about the filter floss in the uppermost basket being dirty which was highly unusual I've never seen that before. There was a distinct circle about 3" in diameter on the filter floss that was very heavily soiled. Bizarre. Usually, the entire surface is uniformly lightly soiled. Also, it was EXTREMELY odd that the sponges were all pretty clean. I remember being shocked by that and didn't understand why that would be the case. Especially the bottom-most and coarsest filter is usually incredibly dirty and vile with waste.

Changes to filter setup:
I was annoyed and confused by the noisy filter operation.
According to my Amazon account the box of Fluval Biomax ceramic media was delivered on March 30th, so they were added probably within a week or two.
In order to free up filter basket space for the doubled ceramic media volume, I removed half (4) of the sponges. Manufacturer default setup is 4 sponges, but I was using 8 sponges (bottom two baskets with progressively finer sponges, upper basket's bottom half filled with ceramic rings with a single layer of filter floss on top).
Next in line I ordered an O-ring kit and swapped out all the old O-rings for new.
Then I noticed micro bubbles in the intake hose and discovered a concealed split seam on a plastic intake tube fitting (not sure if I caused the split when disassembling the tubing or if it was previously there): I ordered a replacement fitting and installed that. I also lubed the impeller with petroleum jelly as well as the hose quick disconnect assembly. Collectively, all of that remedied the gurgling filter noise problem and filter water level problem.

I can't recall if the bloom pre-dated the change of ceramic ring volume.
I do have a recollection that the algae bloom was occurring much earlier in the season than is usual. Unfortunately, no notes on when the bloom began.

Assuming nothing has changed on light coming into tank (windows cleaned, curtains?), I can't think of much else.

Any pattern to when tank got algae occasionally before? New feed, summer peak, filter flow dropping, etc, etc.

Interesting one. Cutting light / adding uv filter I'd do. Big cleans I've never found useful, the algae is always there, some nutrients will be there - it's preventing it from triggering (somehow lol).

The algae blooms I've gotten are typically during the summer.

 

[mimiheart]

My turtle bites sponges and I don't place anything in the tank with him or he'll eat or otherwise destroy it (like plants, etc). He'd not only bite sponges but he'd knock off sections of the RENA/API/FILSTAR XP Filter intake tubing so I had to move to an array of the heavy duty magnetic suction cups to secure the tubing.

How critical is the sponge in the UV rig? Would it be a problem if the turtle decided he wanted to tear chunks of it off?

It's completely removable and probably not that necessary. My fish pick at it, but won't tear it. I mostly keep it in there because it keeps larger particles from getting into the UV sterilizer itself.

 

[Lovegasoline]

It's completely removable and probably not that necessary. My fish pick at it, but won't tear it. I mostly keep it in there because it keeps larger particles from getting into the UV sterilizer itself.

Thanks for the explanation.
Do you think the UV sterilizer would have a shot at working on its own (and maybe I could toss some duckweed in the tank until Mr. T devours it) if I didn't blackout the tank from the sunlight?

 

[Caliban07]

The UV will work on its own. Salvinia or frogbit are other floaters that will do the same job and the may not be as appetising to Mr T

 

[Lovegasoline]

The UV will work on its own. Salvinia or frogbit are other floaters that will do the same job and the may not be as appetising to Mr T

Thanks I think I'll try introducing one of the types of plants. Do you need a lot of plants or will one or two small sections do the job?
I'm also going to look into buying a UV sterilizer. Does it pose any danger for a turtle? Any lights that can damage his eyes or any other health hazard?

I'll also dig back into my filter basket setup ... maybe try removing some of the ceramic media and going back to an 8 sponge vs. the present 4 sponge setup. I'd thought that more ceramic media would offer an improvement in filtration. After all isn't that the main benefit of the larger RENA/FILSTAR/API XP canister filters? I'd assumed that using more ceramic biological media would produce better tank filtration, but maybe I donut understand the filtration system at all