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jpcemc
01/15/2019, 10:36 AM
Hello everyone,

I have been a reef keeper for about two years and I have noticed a concern that I need some outside guidance on. I do regular water changes on my 40G/20G Sump weekly (about 5 gallons a week), I have a skimmer rated for 120G running in the sump, LR in the display and sump a UV filter and a very low bioload (1 Kole Tank 2.5", 1 Yellowtail Damsel 1", and two clowns .75" each). I have quite a bit of coral and a Maxima clam all seemingly doing fine - but my nitrates have continued to climb despite my efforts and light feeding. I do water checks and maintenance religiously. This caught my attention due to one coral losing a head (frogspawn). So I started checking things I hadn't needed to check because they were always nothing.

The only thing I can think of is that I had a canister filter hooked up to offer some extra water polishing. Maybe that is acting as a nitrate factory?

Thoughts? What am I doing wrong? I have my lights running for about 7 hours daily, so no algae to absorb the nitrates.

Dmorty217
01/15/2019, 10:47 AM
Whats in the canister filter?

mattgumaer
01/15/2019, 11:07 AM
What level are your nitrates and how fast are they climbing? I would be surprised if high nitrates are bothering your frogspawn. Not sure there is any good reason to run a canister filter with a sump. In my opinion, they're a PITA to clean and, as a result, don't get cleaned as often as they should, allowing detritus to build up in them. If you want mechanical filtration, add filter socks to the system (if you're not already using them) and change them frequently.

You could also bump up the size of your water changes and/or reduce feeding to see if that helps. If you're changing 5 gallons out of 50, you're only reducing your nitrates by 10% each week. Bump it up to 10 gallons and you're reducing by 20%.

If you want to get 'fancy' you could always trying carbon dosing or bio-pellets but, I think both have a fairly steep learning curve and can potentially do more harm than good. On my 180 gallon tank, I added a Marine Pure block and started carbon dosing when my nitrates were literally off the charts per my Red Sea test kit (at least 64 ppm) and, after several months, my nitrates are now undetectable. However, I think my euphylia looked the same or possibly better with the higher nitrates.

Matt

jpcemc
01/15/2019, 11:12 AM
Whats in the canister filter?

Just filter floss, and other water polishing items. No carbon, etc.

Fourstars
01/15/2019, 11:15 AM
"Maybe that is acting as a nitrate factory"? YES!

Don't make assumptions without checking your nitrate level.

jpcemc
01/15/2019, 11:27 AM
What level are your nitrates and how fast are they climbing? I would be surprised if high nitrates are bothering your frogspawn. Not sure there is any good reason to run a canister filter with a sump. In my opinion, they're a PITA to clean and, as a result, don't get cleaned as often as they should, allowing detritus to build up in them. If you want mechanical filtration, add filter socks to the system (if you're not already using them) and change them frequently.

You could also bump up the size of your water changes and/or reduce feeding to see if that helps. If you're changing 5 gallons out of 50, you're only reducing your nitrates by 10% each week. Bump it up to 10 gallons and you're reducing by 20%.

If you want to get 'fancy' you could always trying carbon dosing or bio-pellets but, I think both have a fairly steep learning curve and can potentially do more harm than good. On my 180 gallon tank, I added a Marine Pure block and started carbon dosing when my nitrates were literally off the charts per my Red Sea test kit (at least 64 ppm) and, after several months, my nitrates are now undetectable. However, I think my euphylia looked the same or possibly better with the higher nitrates.

Matt

I have toyed with carbon dosing but I am really worried about doing more harm than good. I have vodka, but is it harmful to my coral? I took the canister filter off on Sunday and I will test for Nitrates again tonight.

mcgyvr
01/15/2019, 11:27 AM
The term "nitrate factory" is one of the goofiest things in this hobby started by those that really have no idea what they are talking about..
A canister does not make nitrates.. Having a canister does not increase your nitrate level.. A canister does not make food or crap itself..
A canister can be a place where "crap" collects that breaks down into nitrates BUT without that canister the same amount of crap would just settle somewhere else in the tank and the net result is the same nitrate level..

A nitrate issue simply implies your import is greater than your export..
You may be overfeeding the tank..

You may want to look into carbon dosing or other methods to increase the amount of bacteria in the tank..
Its drop dead simple and absolutely no steep learning curve.. and its quite difficult to actually do harm.. I'd be concerned about your own safety and would monitor you putting shoes on,etc.. if you had problems with carbon dosing.. I'd likely take sharp objects away from you,etc..... :p
Carbon dosing can be as simple as adding a set amount of white vinegar to the tank on a daily basis..
I would share an article from this site but I think its down now so lets see if this one is allowed.. http://www.reefland.com/2013/02/13/treating-your-marine-aquarium-with-vinegar-dosing/

jpcemc
01/15/2019, 11:28 AM
"Maybe that is acting as a nitrate factory"? YES!

Don't make assumptions without checking your nitrate level.

I didn't feel that I was making assumptions. I am spitballing to try and figure out an issue. Because with the amount of LR and the low bioload, I was unsure what was causing the issue.

nereefpat
01/15/2019, 11:42 AM
Did you post your test results for nitrate?

lapin
01/15/2019, 11:43 AM
As mcgyvr says canister is not a nitrate factory. What it can do is filter out detritus which reduces nitrate because it get stuff before it can break down. But you will have to suspend the detritus in the water column to allow the filter to work. Another option is to get more filtration bacteria to grow as said above. You can get one of those blocks Marine Pure. They come in different shapes and sizes. They will increase the area your bacteria grows on. You will need to rinse and soak the block for a while. I feel ome of the material dust can harm certain corals. (debatable)

jpcemc
01/15/2019, 11:56 AM
As mcgyvr says canister is not a nitrate factory. What it can do is filter out detritus which reduces nitrate because it get stuff before it can break down. But you will have to suspend the detritus in the water column to allow the filter to work. Another option is to get more filtration bacteria to grow as said above. You can get one of those blocks Marine Pure. They come in different shapes and sizes. They will increase the area your bacteria grows on. You will need to rinse and soak the block for a while. I feel ome of the material dust can harm certain corals. (debatable)

Who sells these blocks?

jpcemc
01/15/2019, 11:57 AM
Did you post your test results for nitrate?

Approx. 80.

mcgyvr
01/15/2019, 12:50 PM
Who sells these blocks?

Numerous sources.. simply google "marine pure block"

They are basically an artificial version of rock.. Its like a foamed ceramic intended to mimic rock and its extensive surface area to increase the space for bacterial colonization..
This may be helpful if you don't have enough rock in your tank.. You can also just add more rock..
Often just adding more rock can be helpful but IMO you won't have much luck lowering nitrates in your situation without carbon dosing (or more water changes,etc...)

lpsouth1978
01/15/2019, 01:02 PM
I recently started dosing vinegar in the same setup you have. I got an inexpensive dosing pump to automate it and have had great results. I simply started at 4 ml/day and ramped it up slowly for a couple of weeks until my nitrates came down. I am now at a low 8ml/day to maintain. I decided that nitrates @ or below 20 has been great for my system. I only have LPS, zoas, mushrooms, and 2 nems, NO SPS.

jmm
01/15/2019, 02:01 PM
The term "nitrate factory" is one of the goofiest things in this hobby started by those that really have no idea what they are talking about..
A canister does not make nitrates.. Having a canister does not increase your nitrate level.. A canister does not make food or crap itself..
A canister can be a place where "crap" collects that breaks down into nitrates BUT without that canister the same amount of crap would just settle somewhere else in the tank and the net result is the same nitrate level.. /[/url]

Bravo on stating this so emphatically and simply. Nitrate is the end result (before nitrogen gas) of the nitrogen cycle. If there were no nitrate, there would be ammonia and nitrite in the water which are far more harmful than nitrate.

Another point: Marine pure blocks in my aquarium are responsible (as far as I can deduce) for undetectable nitrate levels in one of my aquariums. I have nitrates in all the tanks that don't have these blocks. The nitrogen gas "bubbles" out of the blocks.

mattgumaer
01/15/2019, 02:42 PM
Wow. Lively debate. Adding a couple of things:

1) while canister filters do not create nitrates themselves, they can be a place for detritus to accumulate where you are less likely to remove it; think of popping out a filter sock full of gunk versus unhooking your canister filter, opening it, rinsing it out, replacing filter floss, reattaching, priming and putting back in service. In my experience, one is far more likely to be done on a regular basis than the other;

2) as a user of Marine Pure, I have a healthy skepticism of what it does and doesn't do. It clearly adds a ton of surface area where ammonia can be converted to nitrite which then can be converted to nitrate. The big question with this part of the process is whether there is a need for more surface area to grow these bacteria. I suspect that, in almost all cases, the answer is no. There is already plenty of surface area in your tank for the bacteria to colonize. The more controversial question with the Marine Pure blocks is, can they be used to eliminate nitrate from the system in internal areas of the block with little to no oxygen? I think a fair answer is 'sometimes'. In my tank, I started carbon dosing at the same time as adding Marine Pure so, while I feel like the Marine Pure contributed to my successful nitrate reduction, I'm not super confident because I didn't run a controlled experiment where I was changing only one variable at a time; and

3) I don't think carbon dosing is 'idiot proof' but, like many things in the reef hobby, making changes slowly greatly increases the odds of success (and the absence of a catastrophic failure). It seems like carbon dosing can cause 'burnt tips' on acros when running even a moderately high dkh under some circumstances. It also seems like the sudden stopping of carbon dosing can cause problems. Finally, and I may be in this situation right now, sometimes I think you can strip too much nitrate and phosphate from the tank with carbon dosing. In the 'old days', zero was the often stated goal but, remember, nitrates and phosphates are 'fertilizer' so, having some of both is a good thing. I carbon dose with 60/40 mix of vinegar to vodka with a BRS dosing pump but, I did a fair amount of reading before starting the process to be sure I was comfortable with the process. I increased the dose slowly, despite being anxious to reduce both phosphates and nitrates and I did more regular testing of phosphate, nitrates and alkalinity to keep an eye on things while ramping up. I'm happy with my results but, it is one more 'moving part' in my system to keep track of.

Matt

Fourstars
01/15/2019, 03:03 PM
A canister filter is a poop filter and pumps out the nitrate because they don't get serviced enough. Come on guys, this is reefkeeping 101. All my tanks have run for years with zero nitrates with live rock, Cheato, bare bottom and a filter sock cleaned often or just removed.

reefgeezer
01/15/2019, 03:09 PM
Here's my $.02...

Do a couple of 50% water changes to get the drop started. That should get your nitrates from 80 to 20 ppm or so. Carbon dosing will help you from there as long as your skimmer is working, you have some free phosphate in the system, and you go slow. Set the skimmer to skim pretty wet. FWIW I've had the best luck with plain old vinegar.

You really won't need the canister for water polishing when carbon dosing. You'll notice a clearing of the water as the process starts stripping dissolved organics from the water column.

Remember that your're not shooting for 0 ppm nitrate. Cut the dose in half when you get to about 5 ppm and adjust from there.

Fourstars
01/15/2019, 03:22 PM
The term "nitrate factory" is one of the goofiest things in this hobby started by those that really have no idea what they are talking about..
A canister does not make nitrates.. Having a canister does not increase your nitrate level.. A canister does not make food or crap itself..
A canister can be a place where "crap" collects that breaks down into nitrates BUT without that canister the same amount of crap would just settle somewhere else in the tank and the net result is the same nitrate level..

A nitrate issue simply implies your import is greater than your export..
You may be overfeeding the tank..

You may want to look into carbon dosing or other methods to increase the amount of bacteria in the tank..
Its drop dead simple and absolutely no steep learning curve.. and its quite difficult to actually do harm.. I'd be concerned about your own safety and would monitor you putting shoes on,etc.. if you had problems with carbon dosing.. I'd likely take sharp objects away from you,etc..... :p
Carbon dosing can be as simple as adding a set amount of white vinegar to the tank on a daily basis..
I would share an article from this site but I think its down now so lets see if this one is allowed.. http://www.reefland.com/2013/02/13/treating-your-marine-aquarium-with-vinegar-dosing/

A factory is where things are processed on a large scale. Poop in/nitrate out. A ford factory does make fords, it assembles them from raw ingredients. Steel, rubber etc. I would prefer to have it settle in my sump where it can be siphoned or my clean up crew can work on it, instead of forcing all the tank water through it multiple times an hour.

Dmorty217
01/15/2019, 06:30 PM
Siprorax is better than marine pure and doesn’t break down after some time like marine pure will if you have to handle it.

mattgumaer
01/15/2019, 06:56 PM
Siprorax is better than marine pure and doesn’t break down after some time like marine pure will if you have to handle it.

I can confirm Marine Pure can be pretty brittle. I ordered two blocks, one crumbled if you looked at it. BRS replaced that one for me. The other is more reasonable but, still fragile.

Matt

marinelife
01/19/2019, 02:36 PM
I had 3 marine pure blocks and 3 Brightwell bricks, all became brittle. I now only use Siporax in 2 tower filters I made.

FSJGUY
01/19/2019, 03:07 PM
60g hex reef i feed like 2x a day often alot more then i should.

Nitrates are 0-10ppm 24.7 i never have to do water chsbges. I have a homemade canister with 4 liters of denitrate from seachem in them.. running at 40gph (lower flow the better) and in 2 weeks of hooking this up my nitrates were from 40ppm every 4 days and having to do water changes... to 0-10 and never doing water changes.


Sooo tbh this is the easiest way to keep nitrates really low to be honest... no need for a sump no need for any special equipment.. just a zip tie container i added fitting too poured denitrate in.. and sealed it up with silicone and hooked a low flow rate pump too

cwschoon
12/09/2020, 12:59 PM
Reviving this thread.....I am considering adding denitrate to my 120, either in the sump or in some kind of media reactor.
As long as the denitrate in the sump in a low flow area, should I not get the same denitrification benefits, tho it may take longer that if in a reactor?