Help me build the ultimate nitrate-sucking setup

[B1gJ4k3]

Well, let's see how this works...

Of all the "iums" to keep track of, I think this mostly closely resembles a refugium, which is apparently fairly common in the saltwater world, but mostly used for culturing worms and such in freshwater and avoid them getting eaten right away.

I've broken down my 20 gallon quarantine/grow out and and put it next to Casper's 125. For the overflow, I watched a lot of YouTube videos on an overflow system and the one I ended up building out of PVC isn't exactly like any of them, but it probably most closely resembles the one from Blake's Aquatics. I didn't want to limit the flow too much, so I used 1 1/4" PVC and 5/8" ID vinyl tubing across the top. I ended up putting a 90 degree elbow on the inlet to keep the water level up a little higher and above the frame.

The idea of using a spare powerhead to move water out of the small tank and into the big one didn't really work, since that's really not what they're designed to do, so I end up getting a (what turned out to be very small) submersible pump from Amazon. It's much smaller than I thought it would be, but so far seems to be doing the job. It's connected with 3/8" ID vinyl tubing that runs to the opposite side of the big tank, up into an old canister filter outlet tube. The pump is only about 95 GPH, so it's definitely not blasting water out of there, but it's enough.

I've tried to set it up so that if either the pump fails or my overflow loses the siphon, things won't get flooded. Unless Casper somehow hulks the elbow off of the overflow (unlikely), there shouldn't be enough water to flood the 20 gallon and I've placed the pump pretty much as high as I can in the 20 gallon, so that if the overflow loses siphon, it would only pump and= additional gallon or two into the big tank, which shouldn't be enough to make it over the lip. I guess that's the advantage to such a small pump. I am a little worried about the lack of water movement in the 20 gallon, since the flow is so low though, so maybe I'll add a spare sponge filter or air stone or the original power head in there just to get some water movement.

For plants, I was able to find some hornwort and Amazon frog bit locally (Shout out to World of Wet Pets in Beaverton--I just wish they were closer to me). I figured I'd start out small considering how quickly they are both said to propagate. I've covered the top with that plastic light diffuser grid from Home Depot (how versatile is that stuff in fishkeeping, btw???) and then put some pothos clippings from a friend of mine through that so the roots are in the water. @Guppysnail recommended that I try sprouting a sweet potato in the water as well, so I plan to give that a shot.

I've mounted a Fluval Plant Nano above the pothos and I have a spare 18" Current USA LED that I can either put on top of the grid or slip down between the two tanks if the frog bit goes crazy to make sure the hornwort gets some light. Both are on timers for about 8 hours a day.

It's too soon to tell whether or not this will help cut down my water change schedule, but It seems promising so far. I've been pretty impressed with how well the overflow works, too. For an initial test, I set it up in my 75 gallon grow out tank that's across from this one. I threaded a garden hose onto the outlet and used it as an overflow to do probably about a 40-50% water change. It was able to handle the flow that comes out of my faucet, so I'm confident it will handle the tiny pump that's in there now. It was a little nerve-wracking watching my baby platies "investigate" the open overflow, but as far as I could tell, nobody actually got sucked out. So if this experiment fails miserably for some reason, at least I've built a pretty nifty way to handle a simple water change on larger tanks...

I'll keep updating here as time goes on. Normally, it takes about 3-4 days for nitrates to reach 30-40ppm, so I'm hoping that once this gets established, it will be able to stretch it out so that it fits a little better into my existing weekly water change schedule.

[murphy lover 101]

hornwort and duckweed or other floaters.

[KentFishFanUK]

@B1gJ4k3 well we are a week in, how is it going? 

[B1gJ4k3]

@KentFishFanUK It seems to be going OK so far. The tank is still relatively new, so I think things are still getting established. But, previously without this setup, nitrates would get up to about 30 or 40ppm in 3 or 4 days. With this new setup, after 3 or 4 days, it's been reading around 15 or 20ppm, so that's promising. I was going to give it a few more weeks before posting an official update, but so far I'm optimistic that I'll be at least able to cut down to weekly water changes instead of twice a week.

[Bullsnark]

On 8/2/2021 at 3:43 PM, B1gJ4k3 said:

So...I have an idea...

I recently adopted/inherited a very large Central American cichlid. You can read more about him here if you would like. Long story short, he'll pretty much destroy anything you put in the tank with him, be it flora or fauna. He also eats a lot and produces a lot of waste. Consequently, the nitrate levels in his tank stay pretty high. His previous owner was doing 75% water changes every three days to combat nitrates. If I need to do that, I will, but honestly, I would like to avoid it. I think there's a smarter way to handle it.

Obviously, I can't put plants in his tank because they'll get eaten or uprooted. So, my thought was to build a kind of sump system with a spare 20 gallon, put it next to it and just stuff that 20 gallon with plants. I've found promising-looking plans for an overflow that doesn't involve drilling and I figure I can just add a spare powerhead to pump water out of the sump back into the tank, so the engineering of it is not the problem. I'm wondering how I get the most "bang for my buck" plant-wise.

I've got some pothos I can root in there and various stem plants (water wisteria, ludwigia, rotalla, bacopa), but they don't seem great at really sucking up nitrates. I've heard Amazon frog bit is really good, but as near as I can tell, Oregon classifies it as a noxious weed (for good reason), and no one who knows what they're doing will ship it here. I've heard hornwort is also good, but my normal plant sources don't have it in stock. Bamboo could also be an option, apparently. I'd like to avoid duckweed for obvious reasons, but if it's amazing at sucking up nitrates, I guess I could give it a go. What plants would anyone recommend?

And what of lighting? I have no shortage of various aquarium lights, including a few Fluval Nanos. Do I just blast that sump tank with light all day? If algae takes over in that tank, is there a risk of it spreading to the main tank? I don't mind the small tank having algae, but I'd like to keep it out of the main tank if possible.

What are peoples' thoughts here? How can I work smarter not harder?

I think I would go a bit larger than a 20 gallon tank myself and get a couple of big totes to run the plants in. If you use the same concept, but split the flow between two tanks/totes, it would give more time for uptake as well. This is the same basic idea that aquaponics systems use, and some of them can house large numbers of large talapia. With one small pump and float driving the draw from the supply tank, the rest of the system typically runs off of a siphon and gravity to take care of the rest. Media beds that flood can house rooted plants of your choice as well as floating plants in your holding tank from the pump. Check out aquaponic systems on YouTube for additional ideas. 

[Bullsnark]

On 8/19/2021 at 11:42 AM, B1gJ4k3 said:

Well, let's see how this works...

Of all the "iums" to keep track of, I think this mostly closely resembles a refugium, which is apparently fairly common in the saltwater world, but mostly used for culturing worms and such in freshwater and avoid them getting eaten right away.

I've broken down my 20 gallon quarantine/grow out and and put it next to Casper's 125. For the overflow, I watched a lot of YouTube videos on an overflow system and the one I ended up building out of PVC isn't exactly like any of them, but it probably most closely resembles the one from Blake's Aquatics. I didn't want to limit the flow too much, so I used 1 1/4" PVC and 5/8" ID vinyl tubing across the top. I ended up putting a 90 degree elbow on the inlet to keep the water level up a little higher and above the frame.

The idea of using a spare powerhead to move water out of the small tank and into the big one didn't really work, since that's really not what they're designed to do, so I end up getting a (what turned out to be very small) submersible pump from Amazon. It's much smaller than I thought it would be, but so far seems to be doing the job. It's connected with 3/8" ID vinyl tubing that runs to the opposite side of the big tank, up into an old canister filter outlet tube. The pump is only about 95 GPH, so it's definitely not blasting water out of there, but it's enough.

I've tried to set it up so that if either the pump fails or my overflow loses the siphon, things won't get flooded. Unless Casper somehow hulks the elbow off of the overflow (unlikely), there shouldn't be enough water to flood the 20 gallon and I've placed the pump pretty much as high as I can in the 20 gallon, so that if the overflow loses siphon, it would only pump and= additional gallon or two into the big tank, which shouldn't be enough to make it over the lip. I guess that's the advantage to such a small pump. I am a little worried about the lack of water movement in the 20 gallon, since the flow is so low though, so maybe I'll add a spare sponge filter or air stone or the original power head in there just to get some water movement.

For plants, I was able to find some hornwort and Amazon frog bit locally (Shout out to World of Wet Pets in Beaverton--I just wish they were closer to me). I figured I'd start out small considering how quickly they are both said to propagate. I've covered the top with that plastic light diffuser grid from Home Depot (how versatile is that stuff in fishkeeping, btw???) and then put some pothos clippings from a friend of mine through that so the roots are in the water. @Guppysnail recommended that I try sprouting a sweet potato in the water as well, so I plan to give that a shot.

I've mounted a Fluval Plant Nano above the pothos and I have a spare 18" Current USA LED that I can either put on top of the grid or slip down between the two tanks if the frog bit goes crazy to make sure the hornwort gets some light. Both are on timers for about 8 hours a day.

It's too soon to tell whether or not this will help cut down my water change schedule, but It seems promising so far. I've been pretty impressed with how well the overflow works, too. For an initial test, I set it up in my 75 gallon grow out tank that's across from this one. I threaded a garden hose onto the outlet and used it as an overflow to do probably about a 40-50% water change. It was able to handle the flow that comes out of my faucet, so I'm confident it will handle the tiny pump that's in there now. It was a little nerve-wracking watching my baby platies "investigate" the open overflow, but as far as I could tell, nobody actually got sucked out. So if this experiment fails miserably for some reason, at least I've built a pretty nifty way to handle a simple water change on larger tanks...

I'll keep updating here as time goes on. Normally, it takes about 3-4 days for nitrates to reach 30-40ppm, so I'm hoping that once this gets established, it will be able to stretch it out so that it fits a little better into my existing weekly water change schedule.

No filter over the overflow?

[B1gJ4k3]

@Bullsnark The 20 gallon is probably a bit small, but it's all I really had space for and I didn't have to go buy an additional tank. This setup is more than likely temporary as the original owner of the fish should be taking him back at some point.

There's no filter over the overflow because on the tank it's being used on, there's only one fish to worry about and he's too big to get sucked into anything. I had only put it on my platy grow out tank as an experiment to see how it worked and eventually added a makeshift skimmer on the intake after some of the platys got a little too curious.

[KentFishFanUK]

On 8/27/2021 at 5:04 PM, B1gJ4k3 said:

@Bullsnark The 20 gallon is probably a bit small, but it's all I really had space for and I didn't have to go buy an additional tank. This setup is more than likely temporary as the original owner of the fish should be taking him back at some point.

There's no filter over the overflow because on the tank it's being used on, there's only one fish to worry about and he's too big to get sucked into anything. I had only put it on my platy grow out tank as an experiment to see how it worked and eventually added a makeshift skimmer on the intake after some of the platys got a little too curious.

Noo he can't take him back until we know the results of the experiment! 😂