Freshwater ATS discussion

[Andy_cy]

Hi guys, I'm from singapore and over here, freshwater aquariums are much more common than SW ones.

Recently setup my own diy ATS for my 200L tank, it's working very well, having green hair algae growing from day 2 onwards. Just did my first official screen cleaning today, after about 14 days from setup.

I realise that FW ATS doesn't really get very thick, as the strands of GHA just grows longer towards the end of the screen, and may sometimes fall off. My screen is extremely rough, after roughing it twice on both sides, it holds on to the strands of GHA pretty well.

Does anyone know specifically what nutrients does GHA absorb readily? Apart from nitrates and phosphates, is ammonia taken in too? I have been wondering, if the ATS can readily remove ammonia, would it be endangering the beneficial bacteria in my bio filter? Then again, due to the 14-hour light cycle I provide my ATS with, I know my bio filter will have 10 hours of ammonia to itself. So at most, the beneficial bacteria will be starved or competing for 14 hours when the lights come on, isn't it? Big question is, will this harm the bio filter by anyway?

If the bacteria colony shrinks due to the introduction of an ATS, then right after a full cleaning, the shrunken colony of bacteria will not be able to handle the bioload, thus causing traces of ammonia and nitrite for a few days until the algae starts to grow again, right? Isn't that dangerous? Having the livestock exposed to toxic nutrients for 1-2 days every week after you do a cleaning..

Hopefully someone who has experience with FW ATS can help me with those questions. I will post pictures of my ATS soon when I get home.

Currently the main reason for using an ATS is to help reduce my nitrates, hopefully to an undetectable level. Because the rate at which nitrates are produced in my tank is clearly much higher than my weekly water changes can remove it. It resulted in a nitrate level of about 150-200 mg/L. After a week of daily water change, I ended up with about 50mg/L nitrates. Right now, nitrates are reaching 100mg/L again, even though algae is growing like mad in my ATS. I'm just crossing my fingers and hoping that this week's growth can bring the nitrates down a good amount.

All inputs are greatly appreciated

[SantaMonica]

Welcome,

Yes ammonia is absorbed, primarily. It won't alter your bio filter because the ammonia hits the bio filter before the ammonia ever gets to the scrubber. Also, scrubbers add carbon (glucose, etc) to the water which feeds the bacteria even more, making the bacteria even more able to eat ammonia, nitrate, etc.

[Andy_cy]

Welcome,

Yes ammonia is absorbed, primarily. It won't alter your bio filter because the ammonia hits the bio filter before the ammonia ever gets to the scrubber. Also, scrubbers add carbon (glucose, etc) to the water which feeds the bacteria even more, making the bacteria even more able to eat ammonia, nitrate, etc.

Thanks boss.

My tank has 2 pumps, one pumping water into my wet/dry filter, the other pumping water to my ATS. So in my case, ammonia in the water will be supplied to both filters simultaneously, no?

Well, what you said is a great relief to me, knowing that the algae actually boosts nitrifying activities is awesome. Hopefully my ATS can handle the amount of nitrates my fishes are producing.

Other freshwater ATS users please join this discussion and share more experiences!

[Floyd R Turbo]

There is evidence to support the concept that a scrubber has more of a symbiotic relationship with the bacterial colony, rather than a competitive relationship. So I would not worry about the bacterial colony shrinking.

Depending on how large your scrubber is, the nitrates should start to stay lower on a more steady basis.

Walleyefisher is a good person to ask about the specifics of freshwater scrubbers - he has 3 of mine running

[Andy_cy]

There is evidence to support the concept that a scrubber has more of a symbiotic relationship with the bacterial colony, rather than a competitive relationship. So I would not worry about the bacterial colony shrinking.

Depending on how large your scrubber is, the nitrates should start to stay lower on a more steady basis.

Walleyefisher is a good person to ask about the specifics of freshwater scrubbers - he has 3 of mine running

Thanks Floyd.

It seems that the efficiency of a freshwater scrubber is much more limited than a saltwater one. From my observation, a single flat screen can only hold that much hair algae.. Any more and they start falling off. And I don't think it's an issue with my screen's roughness as I am pretty sure my screen is rough as hell! I roughed it so much that some parts of the mesh broke off haha. I'm thinking whether stacking 2 screens on top of each other would help. This way, more anchor points are available for the hair algae to cling onto. Any suggestions?

[Floyd R Turbo]

I think it may have to do with saltwater and calcification. Not 100% sure, but it does make sense - saltwater will form a calcified layer on the screen to which the algae can anchor to. Also I believe that FW algae does grow long and more fine and hair-like, and when it gets longer, it would therefore have more tendency to pull off. Basically, you need to clean more often with FW.

[Andy_cy]

Hi guys, I was hoping more of you who are using FW ATS can post your screens or setups to share with the rest here.
Anyway, here's mine. Just took the pictures in the dark at night, so its not very clear.

This is my screen at day 5 of the 7-day cleaning cycle. Day 5 after its first cleaning. Due to be cleaned in 2 days time.
Quite a lot of green growth, but its fine strands of green hair and it doesn't thicken in width.


This is my setup. Its a custom built glass tank with two pockets for the lights and has two holes drilled on one of the walls
to drain water back into main tank. Each light set has just one 20W LED (warm white) with a big reflector. Its sold as an
outdoor LED floodlight, which is rain-proof.


Although the algae seem to be growing well, its been almost 2 weeks but I haven't seen a significant decline in my nitrates.
How long does it usually take to bring down nitrates to be almost untraceable? Will my screen get any thicker, or is it fully
saturated with hair algae already? Because what I notice is that algae will eventually fall off from the screen, meaning that
there isn't enough space for new strands to cling on? I also intend to DIY 2 sets of LED fixtures to replace the existing one.
Gonna use the 660nm + 455nm setup for maximum growth. But that's not gonna be too soon.

Hope to see more FW ATS builds and pictures. I just wanna learn more about it

[SantaMonica]

FW is much thinner than SW. Without support, the long strands will fall off. Your growth is good though, so it is on the way.

Depending on your nitrate, each screen cleaning could lower it 5 or 10 points.

[Floyd R Turbo]

Try Garf's trick of putting tiny zip ties on the screen. This might give a little support to the growth.

[Andy_cy]

Another week passed but still no signs of lowered nitrate levels
Nitrates at ~25mg/L right after my weekly water change, and tested again before the following week's water change, it raised to ~50-70mg/L.
Experiencing tremendous algal growth, but the test results state otherwise. Is there anything I'm missing out here?
Btw, my 200L tank has one 12" arowana and four 4" datnoides, feeding about 8-10 super worms and 6-8 food sticks daily.
It's just a grow out tank, they will be transferred to an 800L tank later this year.