Coil denitrator?

[JohnH.]

Do these things work?
http://aquaripure.com/
Anyone used one? There are lots of plans to DIY also. Just wondering if it's worth my time...

[AngelMom]

Sounds fishy to me (no pun intended). Anyone who claims you can go months without a water change just wants your cash. Even with low nitrates (and mine are low (always less than 10) due to the large number of plants I keep) you still need to do partial water changes every week or two to make sure that the essential nutrients fish need are repleneshed. Personally, I wouldn't waste my cash...........

[metal-head]

I read in this one book at the library that denitrators (w/e) are still relatively new so not a too many people have them. and that they're like pretty primative so it may require more tweaking than one that they make 20 years from now for example.

Even if you get this there is nothing better than doing weekly waterchanges

[tjigger]

Hey John,
it may work for lowering your nitrates which would be good, and in some cases make it worth buying, but as Angelmom said it won't replace used nutrients in the water.
I'm a SW guy, the corals use about 20 different nutrients in the water, and without water changes they all would not get replaced unles you spend $100 a mth buying chemicals to add them back to the tank(hopefully at the right dose).
The FW plants do not use up as many nutrients so you may be able to go a little longer but I would still do a biweekly or monthly change.

[lloyd berg]

the working principle of a denitrifier is to slowly move the tank water through a coiled tube long enough for the aerobic bacteria to deplete oxygen and thus allow anaerobic bacteria to thrive (in the remaining length of tube) that will consume the remaining nitrates. the 'exhaust' is nitrogen gas and your tank water (that is totally depleted of oxygen).
the only thing that concerns me is the o2 depletion. and (maybe) unknown 'what else' that grow anaerobically.
otherwise it sounds like a pretty easy experiment. a prefiltered (to reduce clogging of the line) power head and a very long coil of black 3/16" line that returns to the tank. i guess you know it's working when it exhausts bubbles of nitro. lol. hardly worth more than a couple of bucks.

[andy1_52]

I would have to say that I agree. This is just a waste of money. I'm definantly not going to be buying one anytime soon... I'm going to be staying with my water changes

[JohnH.]

Thanks, I think I'll just go with an automated water change setup instead. Here's my idea: Run a small plastic line hooked to water supply (tap) through a commercial inline filter (like for an icemaker) then through a section of 1.5" PVC filled with filter floss and activated carbon (a bunch) then put a small needle valve on the outlet (to adjust water flow to add about 8 gallons a week (10% water change weekly). This would feed into the trickle filter sump. Excess water would go out the overflow (bulkhead that I will install into the side of the filter) that is plumbed to a drainpipe under the house. I live out in the country in NW Oregon and the water quality is awesome out of the tap for a community tank. Here's a pic of the filter. What do you guys think?

[doughsing]

How will you get rid of the chlorine and/or chloramines in the water? What about any heavy metals? I don't think the filter you have in mind would remove these things, will it?

[JohnH.]

Also, can I use a small brass needle valve from home depot to adjust the supply water?

[JohnH.]

Activated carbon (AC) will remove chlorine and chloramine. The filter I have described above should have a very slow flow rate (0.0476 gallons per hour). This means that if the 1.5" PVC filter will hold 1/2 gallon of water in addition to the AC, the water will take 10.5 hours to travel through it. This should be plenty of time to remove all chlorine/ chloramine in the water. I will build one to test this, but all of the info I found about AC is that it WILL remove chlorine/ chloramine and heavy metals etc... The key is maximizing the time the water spends in contact with it.

[JohnH.]

Here's a good link on AC:
http://www.wernersponds.com/Activated%20Carbon%20for%20Ponds.htm
Activated Carbon Adsorption in Alphabetical order.
High to very good adsorption on:
Antimony, Arsenic (Treated wood Leaches Arsenic into the Water), Bismuth, Bleach, Chloramines( Chlorine only, see Zeolites for Ammonia adsorption), Chlorine, Chromium, Colors, Dyes, Gold, Hydrogen Peroxide, Insecticides, Monochloramine, Odors i.e. Sulphur, Pesticides, Phenols, Tin, Trihalomethanes.

Good to Moderate adsorption on:
Acetic acid, Cobalt, Detergents, Dissolved Organic Compounds (DOC), Hydrogen Sulfide, Mercury, Ozone, Potassium Permanganate, Silver, Soap, Solvents, Vinegar, Zirconium.

Fair adsorption on:

Copper ( If Complexed), Iron(as FE 3+), Lead, Nickel, Titanium, Vanadium.

Low to no adsorption on:
Alkalinity, Ammonia (See Zeolite ), Barium, Beryllium, Cadmium, Carbon Dioxide, Copper, Hardness, Iron(as FE 2+), Lime, Manganese, Molybdenum, Nitrates, Selenium, Tungsten, Zinc.

[lloyd berg]

thanks for sharing. johnH.
your water change idea is a good one. you won't need to cycle the tank either.

[doughsing]

Sounds good then. That will really cut down on maintenance, eh?

[andy1_52]

You should eventually built this into a "plug and play" system where you could put it all into a box and sell it. I bet if you could really perfect it that it would be a HUGE seller! I know i personally would buy one...

You should keep us all posted on your tests and experiments in this because I'd like to build one actually if it works. Even if I don't end up building one of my own this is still very interesting!

Please keep us posted I beg of you! :CY :CY

[JohnH.]

I will definately post results here. It will be a week or two before I get to it. I work 12 hr shifts so there's no time until I am off work. Besides, I still have a few things to do before my tank is ready for fish.

[lloyd berg]

why not give up the whole filtration system? seems to me it would be just as simple to flush ammonia directly out the overflow and forget the whole cycle/trickle filter hoopla in this set up scenario.

[DevinJM]

Wow, that is what I wanna do on my next tank. It would make life just that much easyer, but I still think that you would need to cycle and all that, cause that much water wouldn't keep the ammonia low enough to justify not cycling properly and using the right filtration.

[JohnH.]

Lloyd,
I might be able to get away with that, but my original goal is just to automate water changes. To eliminate filtration, I would need to flow much more water than my planned 8-10 gallons a week.
After doing a little more thinking about the project, I think I will mix zeolite chips with the carbon. The reason for this is: When activated carbon breaks the chlorine-ammonia bond (chloramine), the chlorine ion is adsorbed in the carbon but the free ammonia passes through. Two things could happen with the ammonia, it could go in the tank, and/or bacteria would colonize the carbon and nitrify it (along with reducing dissolved oxygen). If an ammonia absorbing ion exchnage resin is mixed with the carbon, this small amount of ammonia will be immediately absorbed as it is generated. This will eliminate free ammonia or nitrates from being added to the tank without a reduction in dissolved oxygen (and keep bacteria growth in the filter to a minimum).

[JohnH.]

Oh, I've decided to run the drain to my flower beds on the side of my house instead of the sewer. (I told my wife the aquarium water will give her the best roses in town! and I won't have to water them) I will also add a 'T' , 1/4 turn valve and a hose barb to the drain for a gravel vac. No buckets for that either! I hope this works as well in practice as it does in my head.

[doughsing]

I just wanted to add my encouragement and support for your project. Keep us updated! :)

[lloyd berg]

i would not suggest to eliminate the filtration. it was just an observation tossed into the dialogue.

[DevinJM]

remember John, that a pump will be needed if the flower beds are higher than the sump of the tank.

[oscarbartoni]

If you are filtering the water that is going into your tank that much you might need to add some things that may be filtered out. Also the ammonia will built up in your tank untill it is cycled even if you do a flow through system. Plus how often are you going to change the carbon and the zeolites? If you do not change them often enough they will leach the things into the water that they are supposed to take out. They are like a sponge once they are full they will not hold ( or filter) out these things any more.

[JohnH.]

Devin,
There is a crawlspace under my house which puts my floor about 18" above ground level. I will run the pipe out of one of the vents. No pump needed.

Oscar,
I should get at least a year out of the filter with a flow rate of 8-10 gallons a week (520 gallons/year). Remember, this is 'clean' tap water, not aquarium water that has lots of dissolved organics and other stuff that clogs carbon. Most commercial tap water filters claim over 800 gallons and I will be using LOTS more carbon. Also, refer to my earlier post to see what AC actually removes from the water. It will not alter hardness or Ph. I will use threaded end caps so that I can just refill with carbon and zeolite chips. And to set things straight, this is NOT intended to substitute for filtering or cycling I will follow the accepted tank cycling procedure. This is only to automate water changes and that's it.
Another note, the fish may prefer a gradual, continuous water change rather than the standard drain and refill (maybe I will ask them hehe...).
I'm going to order an adjustable volume flowmeter (rated for 50-250 CCM) so It will be easier to dial in the correct flow.

[JohnH.]

It's finally done!! After spending WAYY too much time under my house, the plumbing for the water and drain are done. I've also put everything but the fish in the tank. Here's some pics.

[JohnH.]

Here's the pic of the drain plumbing. the 1/4" hose is tap water, the lower 3/4" hose goes to the bulkhead on the side of the sump and the 1/2" hose pointing up is the gravel vac. And here's a pic of the big piece of lace rock with caves.

[JohnH.]

Here's a pic of the tap water filter (PVC pipe filled with activated carbon and ammo chips) and drip valve.

[lloyd berg]

nice work. what type of syphon do you use? i noticed a power bar in the background of carbon filter pic. shouldn't you have a drip loop on that?

[JohnH.]

nice work. what type of syphon do you use? i noticed a power bar in the background of carbon filter pic. shouldn't you have a drip loop on that?
Lloyd,
Thanks. There is no syphon, there is a built in overflow in the tank. If you were refering to the sump drain, I drilled the side of the sump and installed a bulkhead. The drip loops are on the side of the sump. The power strip is temporary, I am installing several GFI outlets in a box on the inside of the tank stand. This electrical box will be elevated above the sump.

[lloyd berg]

i thought perhaps you rigged a venturi type syphon using water pressure to suck your substrate junk down the drain that your overflow feeds.
i'm in the planning stages of a 180 for a big foyer that needs to contain all maintenance within the tank and stand's space. no hoses accross the floor and such so i'm looking at a way to put syphon dirt down the overflow and into the plumbing of the bathroom behind the tank wall.
do you anticipate a need to syphon? or is your water circulation/jets taking the responsability of feeding it all into your sump's prefilter?

[JohnH.]

OK, you mean the gravel vac. I just got one that you move up and down in the water a few times to start the syphon.

[JohnH.]

So far, so good. I've been able to keep the drip rate pretty constant. By the way, if any of you wish to try this, 1.25 drips per second will add 10 gallons a week. Everything seems to be working great (I forgot to mention, I made a water trap out of a few short lengths of PVC and some elbows on the drain line). This keeps cold air from outside from blowing in. The main test will be if the drip rate can remain relatively constant and the filter continues to work over time.

[andy1_52]

I'm impressed! my dad is looking into doing a massive 300-500 gallon community aquarium tank in our house so I showed him this post. Now he's seriously thinking about doing it only he wants to use a three cell RO system instead becasue our water at my house isn't good enough.

[JohnH.]

I'm impressed! my dad is looking into doing a massive 300-500 gallon community aquarium tank in our house so I showed him this post. Now he's seriously thinking about doing it only he wants to use a three cell RO system instead becasue our water at my house isn't good enough.

That would work but you would need to mix some filtered tap water with it as straight RO water has NOTHING in it. You need some carbonate hardness to keep your Ph under control. Just run 2 drip systems to get a 50/50 mix or whatever ratio gives you the water you want. A little more complicated but doable.

Also, I did some tests on the tap water going in the filter and coming out. Incoming water measures around 1 ppm total chlorine (slightly pink on the test strip) and the output water has 0 (not even a HINT of color). Ammonia reads zero. I will continue testing weekly to measure the life of the filter. The filter contains about a quart of carbon and a half-quart of ammo chips mixed together.

[JohnH.]

OK, the water change system has been running continuously for over a week. The system is working very well. Here's a list of pros & cons of the setup:

Pros:
1. No hoses, no buckets, no mess, no work.
2. Inexpensive. Roughly $30 including PVC, fittings, carbon, etc...
3. Automatic, set it and forget it!
4. Adjustable. With a touch of the valve, I can set 0% to > 100% water change a week.
5. Continuous water changing system. Water change is gradual and carbon/zeolite filter removes toxins. No need to 'age' the water or bring water to room temp in a large container. Also, traditional methods involve changing large amounts of water at one time. This may stress fish with a sudden change in water chemistry.
6. Can easily plumb the gravel vac into the drain. More buckets and mess avoided.
7. May be easier to keep sensitive fish such as Discus.

Cons:
1. Needs specific equipment. Must have a sump or wet/dry filter and a tank with an overflow (built in or siphon).
2. Complicated plumbing. Needs permanent water tap and connection to drain (Drain connection MUST be lower than level of water in sump). Sump or wet/dry needs to be drilled and a bulkhead installed.
3. The filtered tap water should be compatible with your fish.
4. Need to monitor tap water filter for chlorine. I don't know how long it will last before I need to replace the carbon. I used a lot, so it should be good for at least a year or so.

I would highly recommend this system if you have the means to implement it. If any of you try it, please let me know how it worked out for you. If you have questions, please ask!
-John

[JUDO_BADGER]

Its especially nice if you have a well and don't have to worry about chlorine. Keep in mind that a rubbermaid container can always be used as a sump. This makes the whole thing a lot less expensive. I have such a system planned for my 75 which will have a 50 gallon rubbermaid sump. I will Let you know how it goes.

[JohnH.]

I've been debating whether I should 'turn up' the fresh water flow to keep ammonia and nitrites down to a safe level during the cycle or not. I was thinking if I did, I could significantly delay the cycle. After further thought, I came up with this theory:

A 100% water change per week would be about 10 drips per second, which equates to an equivalent drain of 10 drips per second. Water flow through the filter is between 500-600 gallons per hour. With a total guesstimated volume of water in the system to be about 75 gallons, A particular 'drip' would pass through the filter MANY times before finding its way out the drain. This effectively means only the ammonia and nitrites that the bacteria colony can't eat will be removed from the tank. The cycle time should remain nominal AND the total ammonia and nitrites will remain at a safe, comfortable level for the fish for the duration of the cycle.

Anyone see something I haven't considered?

[oscarbartoni]

If I owned the house that I am in I could do some what the same but as I do not own it and the landlord does not wish me to even put a nail hole in the walls for hanging pictures in the house much less in the garage for building a fish room. I am going to have to build a "free standing fish room" in the garage with fish tank stand (that I am going to build myself) along each wall built from 2x4's. It will be only about 12 x 15 so it will be quite crowded but that is what I will have to work with. There is a dryer vent in the back of the house (that is not being used) that I will drain the used water out and onto the garden. The water will come from a spigit near the garage door and I will have a few hole house filters mounted in the fish room with a few sediment filters and a carbon filter and finally the water will be stored in a couple of 55 gallon barrels (to come up to room temp). I am on limited income and have had a few setbacks so the time table of getting the fish room set up has been set back a few weeks or a month but I will get there.

[JohnH.]

Oscar,

You may not need the barrels. I have turned my water up to 1 gallon per hour (> 200% water change per week) and the aquarium heater was more than adequate to keep the temp constant. (My water comes out of the tap at 42 degrees and may tank is set to 77.) You can go to home depot and get a bunch of that drip irrigation hose with T's and individual plastic drip control valves ($1 for pkg. of 2). Run a main line across your tanks, T off at each with a small section of hose and a valve at the end (put the valve at the end cause they are leaky).

[oscarbartoni]

I am not going to have a constant flow like you but rather will have prefiltered water when I do water changes. I am going to have central filtration systems (two or more) in the fish room. I cannot leave the hose attached to the spigit (especiaaly during the winter), so I will let the water temp come up to room temp in the barrels befor I do any water changes.I have built a few fish rooms and I have gained good knowledge (from previous mistakes) so hopefully this wone will be a lot better than the previous ones.

[JohnH.]

Update:

Hey all, I haven't posted in a while, tank is stable and I've been doing other things. I just wanted to inform those who are interested that the automated water change/ drip system is working very well. Nitrates are ALWAYS less than 20 (and I do overfeed on occasion..hehe), water is always crystal clear, fish are very healthy. I have 2 zebra danios, 9 brilliant rasboras, 9 FAT tiger barbs, a dwarf gourami, 3 miniature plecos (can't remember the name, but they only get 3" or so..), 10 ember tetras, a black ghost knife, an african brown knife, and 5 angels (they were culls, cost $1 each, had deformed gill plates). All fish get along well, NO nipped fins (I must have some friendly tiger barbs!!) Oh, and 2 mystery snails. Here's a quick pic.

[JohnH.]

Here's another quick pic. I had to tape over the flash, then lighten it up in a photo editor.

[Jenn]

I feel like I've just watched an episode of Maggiver.
I suddenly feel the need to booby trap something...............