Can you change too much water?

terrance

Member
I have a 40 gallon and i have a problem with high nitrates. I just did a 25% water change and it decreased a little, so i was wondering if i could do another 25%, and if so, if i should wait a week or so. I dont want to change too much and cause a mini cycle or what not. I would like to do water changes until my nitrates are gone. Is this a good idea?
 

cprdnick

Active Member
Yes it is possible to change too much water. I believe if you wait a week or a little more that it would be alright. You need to trace down the cause of these nitrates first, and possibly come up with a long term fix, such as a DSB or a fuge with some macro in it. It can get expensive having to mix new water every week.
What are your feeding habits.
How many fish do you have and how big is each one?
What are you using for Biological filtration? (LR, LS)?
How long has the aquarium been up and running?
What do you use for top off and what kind of water did you use for initial fill up of the tank?
What kind of salt mix are you using?
 

terrance

Member
I think my problem is having crushed coral. My tank has been set up for about 6 months and i have a dragon goby, a green chromis, brittle star, fire shrimp, arrow crab, and other hermits and snails. My nitrates were at 80, and i did a 25% water change and it went down to 40. I dont have a fuge but i wanted to set one up but have been trying to gather info into getting a hang on one, but i dont have a sump. I tried to vaccum the substrate but i have a lot of rockwork to move them all the time.
 

beaslbob

Well-Known Member

Originally posted by terrance
I have a 40 gallon and i have a problem with high nitrates. I just did a 25% water change and it decreased a little, so i was wondering if i could do another 25%, and if so, if i should wait a week or so. I dont want to change too much and cause a mini cycle or what not. I would like to do water changes until my nitrates are gone. Is this a good idea?

I don't do water changes so to me any water change is too much. NitrAtes around 40ppm will not harm any fish and probably most corals ind inverts. By changing the water you also make changes to all the parameters not just the nitrates. If you add plant life or even just let the algae grow, nitrates will fall by the plant action. Additionally ,the plant life will consume carbon dioxide, buffer ph, and remove heavy ions. If you notice a fall in ph then you definately need more plant life.
Finally, as you have already found, water changes alone will never get nitrates to 0.0 even if the replacement water has no nitrAtes.
 

fender

Active Member
I disagree -- changing the water can fix the problem if the water is part of the problem.
If you are doing water changes with bad makeup water you're not going to help things that way.
I switched from filtered tap/distilled to RO water for topoff and water changes and my nitrates went from 20ppm to 0.
Terrance, what type of water are you using?
 

terrance

Member
I'm using distlled water that i buy from the lfs. I have always used this water, and slowly my nitrates climbed.
 

beaslbob

Well-Known Member

Originally posted by terrance
I'm using distlled water that i buy from the lfs. I have always used this water, and slowly my nitrates climbed.

Sure. All that means is you have livestock in the system and a nitorgen cycle. All totally independant of the input water you are using.
 
I agree with beaslbob; I don't do any water changes to ANY of my aquariums; I just top off with RO water. If your water quality is good to begin with, and with proper chemical feeding, water changes in my experience is unncessary. Too many people has got too caught up in what the LFS has said by doing water changes.
Though many many people will disagree with me, it is based upon my opinion and experience; quite often it's what work for the individual based on informative direction.
Phil
 

jrpage

Member

Originally posted by exotickeeper
I agree with beaslbob; I don't do any water changes to ANY of my aquariums; I just top off with RO water. Phil

I'm interested in how you keep your salinity where you want it?Do you have to sometime mix saltwater and do top offs with that?
 
I built my own filtration system for my 155 reef. First, I have PH & Salinity pinpoint monitors running live. Secondly, when I started the aquarium, I mark the water level line on my sump, indicating where the water should be for 1.023. as water evap. then the water level goes down below my line, then I just add RO water so the water goes back up to the line again. Furthermore, I calibrate my monitors often, and I use a refractormeter to confirm all the readings periodically.
Phil
 
No I don't mix saltwater, because I don't do water changes, I mean I have salt on hand in case something happens, but I don't mix saltwater to put in. Remember, salt doesn't evaporate, only freshwater does. So when the water level goes down, it's the freshwater that has evap. not the salt. Hence the ocean gets salter every year because of the evap. of the freshwater and rain.
Phil
 
I add trace elements daily for idoine, and weekly with calcium and strontium and molybdenum to replenish the elements. I have a dera. tiger striped clam, frogspawn, bubble coral, pulsing xenia, red and metallic and blue mushrooms, with 5 linka stars, hammer coral and much more that is doing EXCELLENT.
Phil
 

jrpage

Member

Originally posted by exotickeeper
No I don't mix saltwater, because I don't do water changes, I mean I have salt on hand in case something happens, but I don't mix saltwater to put in. Remember, salt doesn't evaporate, only freshwater does. So when the water level goes down, it's the freshwater that has evap. not the salt. Hence the ocean gets salter every year because of the evap. of the freshwater and rain.
Phil


Awhile back my salinity dropped for no apparent reason. I assumed it was because I wasn't monitoing it closely enough. But if it doesn't evaporate or "get out" somehow - where'd the heck my salt go?!
tee hee - it's funny now -wasn't then. Lost some inverts that I really liked.
 
Have you been adding mix saltwater to your tank as topping off? Salt could corrode some leaving a white dry flakey residue behine. Thats just dried salt. What are you using to monitor salinity? Remember that the hydrometeres are not accurate, they are off about .2-.3
Is it dropping dramatically, or is it a few points down? Are you measuring the salt right after you change water or during or how long, because after you mix salt up, it can usually drop some points down because it has settle. So an accurate measure would first be not using the hydrometers.
Secondly, to monitor and take water out of your tank, not your sump (just to verify, you normally can take water out of your sump), third, test water on a day you haven't done anything to it, (meaning add or change water).
Phil
 

jrpage

Member
I actually had my water tested at a few LFS's. They noticed the drop about the same time I did.
Bang guy advised me to start upping my salinity with sw top offs slowly and that's how I got it back up. I've since ordered a refratometer (sp) and should be getting it in anyday now.
Hopefully I will avoid having that ever happen again!!:nervous:
 
Hmm, I don't really know why you would need to up your salt content, normally you wouldn't add saltwater to top off, I don't know the chemistry of your water in your area but that's odd, keep us updated, good luck
Phil
 

jedininja

Member
Exotic, ever heard of saltcreep? Salt will exit your system one way or another. I'll bet even Beaslbob has some salt on hand for that purpose.
 
of course I've heard of saltcreep, but unless you have water splashing all over the place, the saltcreep is minimal, (at least it should be); don't get me wrong, I do have saltwater and salt on hand for emeregency as I said in the earlier post, it's just I don't use it, my salinity doesn't drop because of my saltcreep because I have very minimal, I guess salinity could drop due to saltcreep, but it would take a lot of it.
Phil
 

jedininja

Member
Actually, just minial salt creep adds up over time. And if you are always topping of with RO water, your SG will slowly go down. It wont go down much so your fish wont even notice. But I'll bet that if you are at 35SG, in a year you'll be down to 32SG. I'm not debating on whether you need water cahnges, just that salt does leave the system and should be replaced, even if it is a small amount.
 
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