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Discussion Starter · #1 ·
Hello
I am running a nice Nano (12gal) El Natural and I have some mechanical filtration to keep the water looking pretty. Plants and fish are well but increasing amount of thread algae (cladophora?) The filter is just filter fabric sewn up into sock shape thru which water water is pumped. In the tank, pH has recently been rountinely going down and now I find that the nitrates are up to 18 ppm, so I suspect that the filter is hosting nitrifying bacteria. Normally I just rinse it out now and again. But to kill nitrifiers I think I might steam it in the microwave and rinse it again. If I use bleach, I have to worry about getting it all out again.....

What do you think?

Thanks

Peridot
 

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The purpose of a filter is to provide a home for nitrifying bacteria to convert toxic ammonium to non-toxic nitrate. Just do a water change to reduce the nitrate! Some nitrate is ok. Killing those bacteria is the last thing you want to do.

I dought the nitrate or the pH has anything to do with the algae. Lighting and CO2 are more likely the cause of the algae.
Matt
 

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Discussion Starter · #4 ·
Sorry I wasn't clear. I don't mean killing all the nitrifying bacteria in the tank. I just don't want my mechanical filtration to turn into a defacto biological filtration. In this I am following Diana Walstad as closely as I can. "Aquatic plants prefer Ammonium over Nitrates" (page 107) I don't want a biological filter competing with the plants for ammonium (page 111) and driving the pH down. (page 112)
 

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don't worry about this... if there are no NH3/NH4, plants can use NO3.
And I'd assume, plants are much faster at consuming NH3 than bacteria.
 

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Discussion Starter · #7 ·
Yes, I have a natural tank with soil substrate, submerged and floating plants, no CO2, 2 watts per gallon. Basically I have a Walstad type tank. The algae is probably a secondary issue. The persistantly falling pH is more troublesome.

Peridot
 

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I think you need to do some more reading on El natrual tanks. There is no reason in the world ti kill good bacteria. I have an El natural tank and I run a filter on it with a sponge inside the tank on the intake and in the filter itself and I have never had a reason to kill this the bacteria. I think you should post over in the El natural form to try and get some help that way. If you lucky Walstad her self will reply.

Until you get some help I suggest you do a lot more reading in the El natural thread.
 

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Bleach kills everything. Just dump some in your tank, you'll be good. :lol:
Remove the 'sock'. See if you can get your hands on something more porous. A large prefilter where it would be harder for the bacteria to grow. I use a very porous prefilter in my power head, but thats just to catch large debris and is cleaned about every 2 weeks - 1 month under running tapwater.

edit: DON'T DUMP THE BLEACH IN YOUR TANK! :mrgreen:
 

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Discussion Starter · #10 ·
Isn't this the El natural forum!?

Ms Walstad, can you help us? Persistently falling pH is the trouble I am trying to fix. If reducing my population of nitrifying bacteria helped calm down the algae that's good too.

Many thanks

Peridot
 

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Yes this is the El Natural forum. The advice I gave is based off NPT theories. No bacterial filtration.
Falling Ph is caused by lack of CO2. I would guess your filter may be a HOB (Hang On Back), like a biowheel type. Causing surface disturbance, thus releasing what CO2 you may have. This will also affect your Kh because your CO2 is dissipating.

Do a search in this forum for CO2, agitation, disturbance. This should yield some results to help you minimize surface disturbance.

I tried all sorts of things to stabilize my Ph. I finally bought some crushed coral and seem to be doing good now.

Good Luck!
 

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Hello
I am running a nice Nano (12gal) El Natural and I have some mechanical filtration to keep the water looking pretty. Plants and fish are well but increasing amount of thread algae (cladophora?) The filter is just filter fabric sewn up into sock shape thru which water water is pumped. In the tank, pH has recently been rountinely going down and now I find that the nitrates are up to 18 ppm, so I suspect that the filter is hosting nitrifying bacteria. Normally I just rinse it out now and again. But to kill nitrifiers I think I might steam it in the microwave and rinse it again. If I use bleach, I have to worry about getting it all out again.....

What do you think?

Peridot
If the pH is consistently falling, that means that plant growth (pH goes up via photosynthesis) is less than nitrification (pH goes down) and fish load. See my book, p. 5.

Rather than trying to kill nitrifying bacteria, I would try to encourage better plant growth. Better plant growth will bring the pH up and reduce nitrates. It does no good to kill nitrifying bacteria in the filter if your entire ecosystem encourages their activity. You may kill nitrifying bacteria in the filter, but there are many, many more nitrifying bacteria on plants, glass, and gravel layer.

You may need to add more lighting, faster growing plant species, etc to increase total photosynthesis in your tank.

You need to balance fish load with photosynthesis.
 

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Discussion Starter · #14 ·
Thank you Ms Walstad! I think the fog is clearing. I will turn my focus to boosting photosynthesis.

-Not including tails I have about 9 inches of fish in 12 gallon tank and they are on the mellow to moderately active side so hopefully I have not overloaded the tank.
-I may have been over-generous feeding the fish/plants.
-Nitrates were higher than the 17 that I previously posted as I had done a water change maybe a week before; guesstimate 25 mg/l. (water change was not routine; corrected an error I made restoring total hardness)
-Tank is a JRC Nano so the filter is a home-made cloth sock whose mouth hangs open where the foam block would be. It could easily be that it does not have enough surface area to support a significant biological filter.
-Circulation is one submerged pump, no splashing or biowheel.
-There are both rooted plants (including one vigorous weedy one) and duckweed.


To remedy pH, algae and nitrate problems I have done a water change, added a little baking soda, increased lighting to 15 hours, added water sprite to floating plants. I will check how old my bulb is. I will continue to maintain total hardness around 140 mg/l. The total hardness goes down so fast I am wondering about adding shells just to put a floor under it. I do live on the ocean (in Maine). You may not want to ask me about my water source! I am the one who has whole house reverse osmosis as a water source so I have to build my water back up. (usually Seachem Equilibrium) Our well has salt water in it and our taps have RO with a little (10 mg/l) calcium in it.

This is not a new tank. In fact it is 5 years old. It was quite stable until about a year ago until our well went salty and we had to put in the RO system. Interesting.....

Many thanks indeed

Peridot
 

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How much light do you have now? Depending on how much you have you may want to look at adding light, not extending. Your algae problems will more than likely get worse by extending the photoperiod.
I would definitely look at adding shells.

You may need to add more lighting, faster growing plant species, etc to increase total photosynthesis in your tank.
 

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Discussion Starter · #17 ·
I have a 24 watt bulb. The tank is constructed with a partition such that the rear portion is walled off and recieves no light so I would say that that light reached 10 to 11 gallons. I figure 2.5 watts per gallon. I lengthened the duration because in a discussion elsewhere in this forum, Ms Walstad (I think?) recommended it as a way of boosting our favored plants in their effort to out-compete the algae.

I am not trying to get nitrates down to zero. 25 mg/l seems a suspiciously high given persistantly falling pH.

(I should also add that I have a small UV running in case that's relevant somehow)

But who knows ....?......


Peridot
 

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Discussion Starter · #19 ·
Lighting is 24 watt fluorescent 6500k. Earlier I think I called the tank manufacturer JRC, that's wrong, it's JBJ. JRC is stereos, right? Rooted plants grow moderately and are of moderate density, floaters grow like mad and risk shading rooted plants out if I don't thin them regularly. Fish are quite happy so long as I keep the pH from dropping too far. When the corydoras stop dancing around I know I have been lazy about check pH.
 

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Fish can adjust to Ph changes as long as it isn't sudden. My Ph has gone from 8.0 down to 6.0 and is now at about 7.2. All within about 1 year time frame. (Don't ask, was having similar issues controlling Ph :) ) Every single fish came out of it just fine. So I wouldn't be too concerned with your Ph, as long as it's not crashing. Since you've done a water change and made some changes, try riding it out. Let the tank settle down some and see what happens. Sometimes you can do more damage by trying too many things chasing problems. Give it a week, maybe two. Keep an eye on things just to make sure they don't destroy your tank.
 
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