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Nystina

Aquarium Advice Regular
Joined
Nov 2, 2004
Messages
51
Location
CA
Hello Everyone,
I'm afraid i just opened a big can of worms, but after finally realizing i should test my tap water (after having several problems), i discovered my tap water has fairly high Nitrates(20-40ppm). Frustrated with fighting various forms of :2gunfire: algae, i decided to purchase a RO/DI unit.

I have a planted tank, and i have been struggling to get nitrate levels
under 20ppm
My questions are:
1. What water parameters will i have to monitor more closely when i use RO/DI water?
2. Is it better to mix RO/DI with tap water to "lower" some of my tap water parameters such as nitrate and general hardness?
3. -Or- just use RO/DI and maybe add something like seachem's equilibrium to replace lost elements in the RO/DI process?
4. What Elements that were previously "good" in my tap water will be lost and need replacing? Is there a best way to do this?

Tap Water
Nitrate:20-40ppm
Nitrite: 0ppm
GH: 150-300ppm
KH: 40-80ppm
pH:7.8
Phosphate: .5ppm

Tank Water
Nitrate:20-40ppm
Nitrite: 0ppm
GH: 300ppm
KH: 40-80ppm
pH:6.8
Phosphate: .5ppm
Ammonia: 0ppm

Any tips/suggestions/experiences are GREATLY appreciated! (y)
Nystina
 
I bought a RODI unit to lower the hardness of my water. RODI takes almost everything out of the water - which you already know is bad. I mix RODI and tap water. That way there is still at least some of everything still in there (this might be bad). I would assume it would be good to use pure RODI if you add a commercial additive (I assume seachem's equalibrium is specifically for RO water).

More specific answers:
1. make sure KH does not get too low - hopefully above 50ppm (especially if you add CO2
2. & 3. either way should be fine.
4. I have no idea. But method 2 or 3 should put back enough of what you need.

That being said, I would suggest holding off on buying an RO unit - they are not cheep and may not be the best solution to your problem. I would suggest trying to improve conditions for your plants so that they can out compete the algae. (I'm telling you to do this when I haven't got it figured out yet.) People with heavily planted tanks have to add Nitrates to their tanks.

Do you add CO2?
Can you get more and/or faster growing plants?
How long have you had the tank? (often times algae goes away over time).
 
With >2.5 wpg and co2 the NO3 will be not really a big issue. As mention above, in a proper planted tank, not enough NO3 is very common.
It would help if you can let us know following:-

1.What is your wpg?
2.do you add co2 into the tank?
3.what fish you have in there?
4.how long do you light the tank?
5. what do you feed your tank and how often.
6. Pls let us know your filter type.

Dont buy the RO unit 1st, spend the $$$ on the lighting and C02 would be wiser, of course unless you have $$$ to burn.... :D

The RO water and conditioner will be very $$$ in long run.
 
I agree - if your plants are healthy they will suck the NO3 right out of the water. If my tap had nitrate I would not have to dose NO3 like I do now, but would simply do a water change.

I don't know how NO3 impacts your health in terms of it being present in your drinking water, though. I guess you must have some way healthy house plants - they will love nitrate water!
 
Hello everyone,
Thanks for all your advice.
Here are the answers to your questions

1. yes, i do have a pressurized co2 setup

2. faster growing plants.......i could always add more/change some with faster growing plants, but i'm not sure what you mean by "fast growing"....Fastest growing plant i have is cabomba(grows like a weed)

3. well.. i've had the tank for 9 years, i just changed the substrate recently to eco complete because i'm just getting serious about a planted tank. I believe this did not disrupt the bacteria too much, i did the gravel change in stages and i haven't had any ammonia spikes

4. 4 wpg (fairly new lights....i know there is a break in period but i've had algae problems on and off for a long time)

5. fish: 3 angels, 12 tetras, 1 gourami

6. 11 hr. photo period

7. I feed mostly ocean nutrition formula one/two, once a day. Occasionally supplemented with bloodworms/brine/blackworms. I don't really feel i overfeed... no food reaches the bottom of the tank.

8. Emperor 400 filter, just the blue pad thingy(took carbon out), and filter floss(might add some bio media instead)

50 gal tall tank, i do water changes 1-2x a week (more recently every other day to prevent algae bloom, i already have a fuzz algae outbreak i'm battling)

My rationale for purchasing the RO/DI was my tap water is bad to begin with.....no matter how many water changes i could do i wouldn't be able to get my nitrates down to 10ppm. Maybe i'm wrong though.. that was my reasoning. I also considered buying a better filter.. one with more media capacity, but i thought a RO/DI would be a better solution rather then fighting my tap water after ever water change(the RO/DI unit is actually cheaper than the filter).

Thanks again for all your help!
Nystina :D
 
Honestly, I agree with other members that getting an RO/DI unit is not the right move here. First, I'd definately get some more demanding plants. They will really love that tank and will eat up the Nitrates pretty fast. Cabomba is good but there are more demanding plants you could have.

Secondly and more importantly imho.... Your problem is right here:

Nystina said:
5. fish: 3 angels, 12 tetras, 1 gourami

You have no algae clean-up crew in that tank. With a heavily planted aquarium you really should have a number of various algae eaters. I'm not surprised you are having algae problems without a clean-up crew. Look to get some workers in there such as: Otos, Bushynose Pleco, Florida Flag Fish, Snails, etc. Let them do the work for you. :wink:
 
With CO2 injection and 4wpg you are really going to need to be dosing ferts as well, like iron, potassium, possibly phosphate, etc., because you are likely to have an algae problem that no algae eater will solve without them, as I only know too well. I have 3 ancistrus and 3 American flag-fish in my 55 and if I get a bit lazy and skip some dosing all kinds of algae heck breaks loose in there- I am constantly battling algae.

I think this is turning into a "how to I get my plants to uptake the free nitrate" instead of a R/O thread. Agreed, your water may not be the best, and if that is the case you might consider R/O for your own health, but I don't think the nitrate is the core of the issue.

Maybe get yourself some hornwort and water sprite, also hygro is a great stem plant that grows like crazy.
 
Why not try adding 3-5 SAE and 1-3 oto into the tank? I think both are the best aglae eater for planted tank due to their small sizes. but once added to the tank, pls give them 1-3 weeks to totally control the algae as unlke chem treatment the biological treatment take sometime before showing result.

Just to share with you, my 32 gal i have 5 SAE, 2 oto and 6 amano shrimp as my cleaning crew. other then the green spot algea, i could hardly find any other algea in the tank.

If you are using auto timer for the light, you can adjust the timer to switch off the lighting for 1-3 hour in noon as algea prefer long constant lighting condition.

Btw prior buying any SAE, do some reading on them as there are few look alike which dont eat algea as they do. Dont get the CAE.

HTH
 
Hello again,
Well where should i start..
My primary concern is the well being of my fish. I don't want to add 20ppm of nitrates every time i do a WC. I'm trying not to stress out my fish/plants any more than need be. But on the other hand... I'm a little worried about my KH after RO/DI... i don't know what problems that I will stir up with my co2 injection.

I also thought that it would be easier to maintain the optimum ratio of nitrates/iron/phosphate/potassium if i could control my water a little better. I thought this would eliminate the algae?? But, it's hard to reach that ratio when one of the elements is way off.

I thought about adding 3 SAE's, however i was unable to find them at any LFS, only the similar CAE (bad.. i know) I also thought that the increased fish load would just increase my nitrate problem so i sorta abandoned that idea. I already have some more plants due to arrive in a few days...glosso and some more rotala indica... hopefully those will help a bit.

Oh.. i already turn off the light for 2 hours mid-day. ( i search these forums constantly for ways to solve my problems.. that was one of the many great ideas i found here )

Anyhoo... the truth is, i wasn't expecting everyone to disagree that a RO/DI wasn't the best decision :? I already ordered it before i posted this so.. unless i resell it on ebay, i'm stuck with it. Seems like you all are trying to forewarn that this will not be the solution to my problems :(

It sounds like algae is just to be expected with this kind of tank.

Finally... i trust you all more than i trust any fish store, so, if you say some SAE's are the answer, i will try to find some. I don't know about the added plants though....i'm trying to come up with a way to fit those into my tank. :wink:
 
IMHO, the <40 ppm NO3 in the tap water may not be the best water but in your planted tank, i think it should be fine as you are have 4 wpg and CO2.

U may want to consider adding some algea cleaner into the tank for the algea problem.

Btw, as mention by TG, in order for the plant to use the NO3 in photosintesis, they also need other nutrient such as Fe,etc. What fertilizer did you add to the tank?

HTH
 
Focusing on human health here...

Nitrate in your drinking water should be avoided. The EPA considers nitrates above 10 mg/l (10ppm) not to be safe. I would definitely get your water tested professionally. Carbon filters will not help here, you will need RO, ion exchange, or a distiller. If you're on municipal water, raise a big fuss.

Nitrate can be converted to nitrite by bacteria, as we have all seen in our tanks. Babies under six months old are particularly subject to problems because of nitrites. Nitrates can be converted to nitrites in their guts, which then oxidizes iron in the bloodstream and can lead to methemoglobinemia, or "blue baby" syndrome. Babies have higher pH in their digestive tracts and low concentrations of the enzyme in their bloodstream that deals with nitrites binding to hemoglobin. Also, there is some evidence that nitrates in drinking water are correlated with some types of cancers and spontaneous abortion.

Deal with this. Please.
 
Ya... i know my water is bad... i didn't even mention the high chlorine/chloramine levels... Good 'ol Los Angeles water!

As for the ferts, i use 2, kent freshwater plant and freshwater essential. They both have small amounts of iron/potassium.. this is only temporary though, i'm waiting for my seachem additives to get here.

And i finally found a LFS that sells SAE's (i hope anyway, they said they will get them in next week)

I think i'm gonna mix about 50/50 tap/RO water for a while and see how that works... at least until i have to start dosing nitrates. Hopefully i will start to believe i'm headed in a positive direction.

Thanks again for your advice everyone!
Nystina
 
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