High Nitrates have me stumped

[Daxster]

We have a 30 gallon tank thats been running for 3 months. It feels like it took a long time to get all of our levels at 'good' ranges, but we are still struggling with high Nitrate levels 40-80ppm. We do 10% water changes weekly and 25% change monthly. I have tried adding a AQI Nitrazorb filter media bag to our filter with no change.

We are very careful not to overfeed, feeding 2x per day very small amounts and watch to make sure no food falls to the bottom. I was using the gravel vaccuum wrong, but learned how to use it right and used it yesterday with a 20% water change. I tested today and still had an 80ppm reading. I have tested our tap water which reads 0. I can't figure it out.



Here's our stats:

30 gallon tank that was a kit with heater and Marine land filter: using carbon filter, bio wheel and nitrazorb bag

6 live plants, some green algae just starting to dot the glass

3 zebra danio (1.5 inch each)
1 red tail shark (2 inch)
1 fancy guppy (1.5 inch)
1 dalmation molly (2 inch) She was pregnant when we got her which we didn't know, saw a couple babies but they disappeared
1 pleco (1.5 inch)
1 bamboo shrimp
1 tiny snail (came with a plant)

Thanks for your help!!

 

[blue_ram]

Wash out the filter media in old tank water. Also do you clean the gravel when you do water changes?

 

[nanu156]

ok, feed 1x every other day till you get balanced out again... Then feed 1x/day

rehome the pleco and redtail shark (they will outgrow your tank and the redtail will get super mean)

Wash out the filter pads in the dirty water after you vacuum

do 25% minimum weekly changes

you are not changing enough water and I think you are still overfeeding, fish aren't dogs they don't need to eat twice a day.

 

[lauraf]

Yeah, bigger water changes. If your nitrates are at 80ppm, and you change 25% of the water, your nitrates will only dip to 60ppm. Do another 25% water change right after that, and your nitrates will still be at 45 ppm. Try a few 50% water changes, washing your filter media in dirty water as suggested above - DO NOT change out your filter media for new ones.

 

[Daxster]

Thanks for the tips. Unfortunately, I already changed the filter media. The filter has 2 slots so I ran the old one and a new one together for a week and just took out the old one.

I will try another 25% water change today. How much is too much with water changes? How much and how often can you do? Our lfs warned about changing more than 30% at one time.

Our lfs also told us to feed 2x per day. They are also the ones who convinced us to get the pleco & red tail shark. They said the pleco would be ok with the shark and that they would only grow to the size of the tank.

 

[IThinkTherefore]

Fish that grow to the size of the tank are stunted - their skeleton stops growing, but their organs continue to increase in size, leading to a painful death.

More likely, though, they just get too big. We see lies from the LFS every day, trust them like you trust a used car dealer xP


You don't have any fish that will ever need to eat more than once a day at most. Every other day is fine, or break it up into one smaller feeding each day.

 

[nanu156]

Thanks for the tips. Unfortunately, I already changed the filter media. The filter has 2 slots so I ran the old one and a new one together for a week and just took out the old one.

I will try another 25% water change today. How much is too much with water changes? How much and how often can you do? Our lfs warned about changing more than 30% at one time.

Our lfs also told us to feed 2x per day. They are also the ones who convinced us to get the pleco & red tail shark. They said the pleco would be ok with the shark and that they would only grow to the size of the tank.

Ummmm did you just answer your own question there? I don't know why but this is universally true, people working in fish stores are famous for
-making $hit up
-outright lying
--misinforming

fish can become stunted in small tanks, when this happens their organs continue to grow until the uneven growth of exoskeleton and internals is too much then they die a horrible deformed death...

2x day feeding is to sell you more food. But also because they likely aren't real knowledgeable.

I don't know what their warning was but when changing your tank water you can get really aggressive with it, like 50-75% if you really want to. The tricky part is that it is also an important to keep the water the same temp as the tank.

also don't ever change a filter pad again, unless it is literally falling apart. just wash them in the bucket of dirty fish water after you clean your tank. They tell you to change them because the highest profit margin is on dry goods particularly filter media.

 

[lauraf]

Do. Bigger. Water. Changes.
It's okay. The good bacteria is in your filter, gravel, etc, not so much in the water itself. As long as the new water is the same temp and has been treated with a dechlor, bigger water changes will help, not hinder.

 

[Daxster]

Water Changes How Much is Too Much?

Thanks for all the advice everyone!

Nitrates are still between 40-60ppm

Friday we did a 20% water change(with a gravel vaccuum) and then after the info here we did a 30% water change(with a gravel vaccuum) Sunday. Does that equal 50%? I know that probably sounds dumb, so I guess my real question is how much is too much and how close together can they be?

We have done so much gravel vaccuuming(the right way now that I know how) in the last 3 days, should these just be straight water changes?

 

[OrangeCones]

Friday we did a 20% water change(with a gravel vaccuum) and then after the info here we did a 30% water change(with a gravel vaccuum) Sunday. Does that equal 50%? I know that probably sounds dumb, so I guess my real question is how much is too much and how close together can they be?

As long as the new water is matched for temperature, and properly dechlorinated, you should be able to do daily (or even 2x daily in emergencies) water changes with no ill effects.

As for your math question: You have not quite done a 50% water change with a 20% and a 30%. When you did the 30% change, you took out some OLD and some NEW water.

You have a 30 gallon tank, so when you did a 20% change on Friday, that left you with 24 gallons of OLD water, and 6 gallons of NEW water.

On Sunday, you did a 30% water change. That would leave you with 21 gallons of a mixture of OLD and NEW water, and now 9 gallons of NEW water.

You have added 15 gallons of NEW water overall, but the 2nd water change took out 30% of your 1st water change's NEW water.

Started out with 100% OLD water.

Friday, changed it to 80% OLD water, 20% NEW water

Sunday, changed it to 56% OLD water, 14% NEW(ER) water, 30% BRAND NEW water.

It makes it effectively a 44% water change.

I never knew algebra and word problems would come in handy as an adult!

 

[nanu156]

LOL Cones that was some great math!

Water can't really be too clean, just make sure not to disturb the filter pads, DO NOT CHANGE THEM unless they are literally in bits then only change one at a time, (if you have a single pad then you need to float the old one in the tank (Toss it in a panty hose to keep it from falling apart while it floats and it needs to float in the tank for 1 week while the new pad gets some bacteria built up.

 

[OrangeCones]

LOL Cones that was some great math!

Thx

Water can't really be too clean, just make sure not to disturb the filter pads, DO NOT CHANGE THEM unless they are literally in bits then only change one at a time, (if you have a single pad then you need to float the old one in the tank (Toss it in a panty hose to keep it from falling apart while it floats and it needs to float in the tank for 1 week while the new pad gets some bacteria built up.

Rather that just tossing the old pad in a panty hose, I've always first taken the new pad and old pad and rubbed them together to get the new pad 'dirty' with as much buildup as I can. Basically what I would be removing by swishing the old pad (if I were keeping it) in old tank water before replacing it back into the filter is now coating the new pad. Then keep the old in the tank but not IN the filter to help transfer as much to the new pad as possible. I've kept the old pad in/near the outflow of the filter to keep it aerated as much as possible.

 

[Dylandrewsdad]

. I do 50% weekly, I have when there is an issue changed 50% daily. Clean water i what's best for your fish. And I didn't read all of OC's post, but while 20 + 30 = 50 what you did does not equal a 50% water change

 

[nanu156]

Yeah, there are lots of options, honestly if its not dropping bits of it's self off into the water you don't need to put it in the pantyhose. Some filters (like whispers) have room for 2 pads and then just sneak the new one in behind the old.

I don't know it's all personal preference. I use Aquaclears now so I don't replace pads

 

[OrangeCones]

I have one HOB filter that I don't use, have for emergencies in a non-planted q-tank. Otherwise, I use only sponge filters driven by powerheads. I slice them all in half horizontally and take 1/2 of a sponge to start new tanks, or can 'stuff' it in the filter space of the HOB filter to instantly cycle a q-tank.

I don't even know what brand it is! Came with a 'kit' for a 29gallon tank, haven't used it in over 18 months.

 

[Daxster]

Improvement! + 1 crazy Danio

Ok so after OC's math lesson(thanks OC!) I did another 30% change yesterday and today was between 20-40ppm. I'm not great at reading the test water vs. the card but it was definitely much better than before.

I did a 50% water change today in hopes of getting squarely in a safe range. Once that happens how long before I know if it's stable?

Also, every time I'm working in the tank or siphoning I have one danio that insists on poking me. It's a nosy little thing too, today he swam up the siphon which was pointed into the corner of the tank and ended up in the bucket.

Is this normal for Danios? I wonder if it's because I don't have enough of them? I checked Aqadvisor and it said minimum 5.

I was debating about rehoming my red tail shark I saw some advice here that said my tank was too small and also saw in the same thing aqadvisor. The thing is we are moving to a house in 3 months and we will be able to get a 55gal(I want a 72 but that is yet to be discussed with my other half) and the shark is still little at the moment.

My 30g
3 zebra danio
1 red tail shark
1 fancy guppy
1 dalmation molly
1 pleco
1 bamboo shrimp

 

[Dylandrewsdad]

You should be OK then, as long as you get the 55 then with the RTBS and Pleco. When you get the bigger tank you will need more danio's and either guppies (my choice) or Mollies.

 

[nanu156]

yeah fish will do that, i find if i set a net in the tank everyone steers clear of where i am working and hides out as not to get netted.

 

[Daxster]

Going to do another 50% water change today, nitrates are still reading at 40ppm. I just don't understand it, the test water looked between 20-40, closer to 20 yesterday than today and that was before the 50% change I did yesterday.

 

[Dylandrewsdad]

Are you shaking the snot out of both bottles?