Water test

[Dora]

I have a 20 gallon freshwater aquarium with 8 glowlight tetras and 7 coryadoris catfish. I did a 5 gallon water change with treated tap water about 5 days ago. When I tested the water today, the alkalinity has gone from 40 to 0, the nitrate has gone from 80 to 60 (although it's normally around 40), and the Ph has remained stable at around 6.5.

I don't if those numbers are okay since I basically check for any unusual changes. The drop in alkalinity is unusual and the 60 nitrate still seems too high. Can anyone suggest whether or not I should do another water change? If so, is it okay to do it only 5 days after my last water change and how much water should be replaced? I usually do a 5 gallon change once a month.

The only thing I did differently in this last water change was that I took the grid out of the Millennium 1000 filter and gently swished it in the bucket of tank water to loosen up some of the larger debris during the water change. I've been using that filter for almost two years so there were a lot of particles on it. Someone at the tropical fish store advised me to do that. Now I'm wondering if his advice was wrong.

Any advice will be very much appreciated.

 

[tropicfishman]

your prolly wanna replace the filter cartridge, you prolyl have to much build up on it, you should change them about every 2- 3 months, as for your water levels, most will flaucaute over time with water changes considering there is nitrates in tap water anyways. instead of doing a bunch of water changes you could buy some Denitrate to take care of ammonia, nitrates, and nitrites, you can mix it in the gravel or put in your filter

 

[Dora]

Thanks, tropicfishman.

I'm a little reluctant to introduce new chemicals into the tank. Could there be any adverse reactions with Denitrate? Maybe I'm just being paranoid. 8O However, I did replace the filter cartridge.

Because levels fluctuate over time, do you think my numbers are within the acceptable range? If so, I'm tempted to leave it alone until the next scheduled water change.

My fish are from an Amazon environment and prefer more acidic water (I hope I remembered that correctly) so maybe the loss of alkalinity (from 40 to 0) is not a concern. Also, the nitrate is slightly higher than after usual water changes (60; normally 40) but is within the "safe" zone according to my test kit. Maybe I am just overreacting...at least I hope so!

 

[Zagz]

I've had no experience with chemicals to remove ammonia, etc. I personally don't use them. I believe water changes are the way to go. Nitrates of 40ppm are still too high IMO. How often are you doing water changes? The filter media needs to be changed more often. You don't have to use carbon, you can use filter floss instead of carbon. I would do another pwc to get the nitrates under 60ppm.

 

[Devilishturtles]

I agree with Zagz.

The reason your Nitrates are so high is because you only do water changes once a month (and sometimes so do I, but they should be done more often). Every two weeks is usually a good schedule to follow. Your nitrates are so high because of this. Doing a 50% water change would drop your nitrates now from 60 to 30, and you'd be alot better off. Maintain your water changes at every two weeks and they shouldn't climb much over 40. Btw, nitrates aren't a toxic thing to fish, but they do do harm in the long run, especially causing your fish to not grow or grow very very slowly.

instead of doing a bunch of water changes you could buy some Denitrate to take care of ammonia, nitrates, and nitrites

Sorry, I'd have to seriously disagree with this. Chemicals are worthless and do NOT work. A water change on a 20 gallon tank cannot take more than 15 minutes to do. Less expensive than adding chemicals and the fish will love you more for it too.

 

[Dora]

How often are you doing water changes?

I've been doing a 25% change once a month.

I would do another pwc to get the nitrates under 60ppm.

I feel more comfortable doing that.

The reason your Nitrates are so high is because you only do water changes once a month (and sometimes so do I, but they should be done more often). Every two weeks is usually a good schedule to follow. Your nitrates are so high because of this.

Thanks, devilishturtles! BTW, do you remember me? I was the one you helped through the euthanasia ordeal back in April. I appreciated that so much!

Doing a 50% water change would drop your nitrates now from 60 to 30, and you'd be alot better off. Maintain your water changes at every two weeks and they shouldn't climb much over 40.

Thanks. I didn't realize that. Is it okay to do a 50% water change only 6 days after a 25% water change? Also, can I get away with changing less than 10 gallons? Half the water seems like so much.

 

[IceH2O]

Looks like you're heading for a pH crash. Alkalinity ( KH ) dropping isn't a good thing.

The bacteria in your filter use KH. When they use it up the pH crashes which in turn kills the bacteria.

You only need to replace the cartridge when its to dirty to clean. I use a cartridge filter on my 20 gallon but I added a sponge to the bottom and only have half the cartridge in the filter. That way anytime I change the cartridge or wash it out really well the sponge still has bacteria that keeps the tank from cycling over again.

Its only a 20 gallon tank, I do 25% weekly on mine but it has a small fishload. 25% a week would help you keep the KH up, keep the nitrates down and your fish happier. If you're fishload is bigger 50% weekly would help.
Owners of Discus usually change 50% of the tank water daily so you coan never do to many water changes.

Don't waste money on chems, they hide the problem they don't fix it.

 

[Dora]

Looks like you're heading for a pH crash. Alkalinity ( KH ) dropping isn't a good thing.

That doesn't sound too good the way you put it. What exactly does that mean? Can PWCs prevent the crash or am I in for mucho problemos?

Its only a 20 gallon tank, I do 25% weekly on mine but it has a small fishload. 25% a week would help you keep the KH up, keep the nitrates down and your fish happier. If you're fishload is bigger 50% weekly would help.

I have 15 small fish (glowlight tetras and coryadoris catfish). Is that considered a small fishload for a 20 gallon tank?

 

[IceH2O]

Doing water changes will refresh the KH and help keep it stable and keep the pH stable.

Thats a pretty heavy fishload, maybe even overstocked IMO. You'll be better off doing 50% water changes.

 

[Dora]

Doing water changes will refresh the KH and help keep it stable and keep the pH stable.

Thats a pretty heavy fishload, maybe even overstocked IMO. You'll be better off doing 50% water changes.

Thanks. I didn't realize 15 small fish is a heavy fishload.

I just changed 1/3 (7 gallons) of the water because I only had seven gallon jugs with pre-treated tap water on hand. I know AmQuel and NovAqua are supposed to work instantly but I'm afraid to test out that theory on my own. I've always pre-treated tap water ahead of time and stored in gallon jugs for future water changes. Soon I'll be adding three more gallon jugs to my collection to prevent future shortages. Is that silly? How do other people do it?

Is it correct that it takes three days for the water to cycle and that's when I should check the water again for an accurate reading?

 

[SCFatz]

I just changed 1/3 (7 gallons) of the water because I only had seven gallon jugs with pre-treated tap water on hand. I know AmQuel and NovAqua are supposed to work instantly but I'm afraid to test out that theory on my own. I've always pre-treated tap water ahead of time and stored in gallon jugs for future water changes. Soon I'll be adding three more gallon jugs to my collection to prevent future shortages. Is that silly? How do other people do it?

Just get the tap to temp and start filling bucket/jugs.Add the declorinater as you fill.

Is it correct that it takes three days for the water to cycle and that's when I should check the water again for an accurate reading?

That will depend on the amount of circulation I would suppose....But I think a couple of hours with just adequate fitration should yield accurate results.

 

[Dora]

Thanks, SCFatz.

It's been more than a couple of hours so I just tested the water and here are the results:
40 Nitrate
0 Nitrite
20 KH (Alkalinity)
7.2 pH (approximately--it's hard to tell with the strip)

The water is still a bit cloudy. I usually don't notice that after 5 gallon changes. Do you think the cloudiness is okay?

 

[Devilishturtles]

I do remember you, glad to have helped you out and glad to hear your tank is going well!

My water always looks a little cloudy after I change it, from stirring up debris and such. If it doesn't clear up by morning I'd be concerned but it's likely just settling.

 

[Dora]

Thanks, Devilishturtles.

Unfortunately there is still some cloudiness in my tank this morning. I'm wondering if it might be a bacteria bloom. That happened to me last year when I first set up the tank.

In hindsight, I think I shouldn't have swished the filter's grid in the bucket during last Monday's water change. It probably got rid of too many of the helpful bacteria. Three days later, I replaced the filter cartridge, ridding the tank of even more bacteria. Then the water change removed even more bacteria. At least, that's what I think happened.

This morning, all the fish seem to be doing okay and the cloudiness is very mild. I'll keep my fingers crossed that when I get home from work there won't be any major problems.

 

[Devilishturtles]

Sounds like a small bacterial bloom. Test your water. As long as ammonia and nitrite are still undetectable then I'd give it a few days to catch up on itself. You are probably right, in that you disturbed too much of the good stuff too quickly. Keep us updated, please.

 

[Dora]

Water's still a little cloudy. Just did a water test and found my alkalinity is back down to zero and pH is around 6.0! 8O

What should I do? Will the low alkalinity and low pH cause a disaster? Should I resort to buying a chemical to raise the pH? Last summer, during a bacterial bloom, I bought some precultured ceramic rings from the tropical fish store and the cloudiness cleared up overnight. Does anyone know if that would help or are there any other suggestions?

Oh, and will these current conditions harm my fish?!

 

[Dora]

Here's an update--the pH was a little higher today (6.2) although there is still some cloudiness. I took a water sample to the tropical fish store and spoke to one of the guys I trust. He said the cloudiness wouldn't be from a bacteria bloom because there aren't any nitrites or amonia in my water. He thinks the cloudiness is related to the pH being unstable.

He said I could wait for the pH to go up on its own with PWCs but that might take a long time and it could affect the health of my fish. He sold me a 7.0 pH buffer that I'm still sort of afraid to use because I try to avoid checmicals if I can. Has anyone here used pH buffers and are there any adverse effects?

 

[Devilishturtles]

I've never used a pH buffer before, but have heard from others that they are notorious for causing it to flucuate too much.

I would keep doing daily water changes for now. You need to up your alkalinity, KH. Otherwise your pH is going to keep swinging all over the place. Alkalinity is sorta what keeps your pH stable.

Adding the chemical is up to you. Your pH is on the rise slowly, so I personally wouldn't add it.

 

[tropicfishman]

when my tests show high nitrates, ammonia, or nitrites, I will do 10- 20 % water changes daily until they fall, given I give the tank 24 hours before each testing to insire accurate test results

 

[Dora]

Thanks, Devilishturtles and tropicfishman.

I haven't used the pH buffer yet. On the other hand, I'm afraid to do another water change right away because the white cloudiness happened after my last PWC. 8O Also, the pH fluctuated from 7.2 to 6.0 and then to 6.2 after the PWC. Right now, the pH is lower (6.2) than it was before the PWC (6.5). Could that have been a result of the PWC or could it be a coincidence?

I'll check the pH/KH readings when I get home from work tonight and then make a decision. :?