High Nitrates and Mini Cycling Question

[Graft]

I'm new to this board, so I'll just say "hey" to start off with.

I'll start off saying that I'm not new to fish keeping. I used to keep fish about 8 years ago and I think my success must have been due to being lucky. The only deaths I had were due to the city adding chloramine to the water without my knowledge and going away to school.

With my history I thought I was well educated, but I'm going to post as a beginner because I've done some stupid things that I shouldn't have.

I bought a 37 gal tall tank, cycled it about 9 months ago and have been keeping fish since. Well, I had a bunch of deaths about 3 months ago and had no idea what was going on. I went out and bought some more "replacements" and they died fairly quickly (within a week). I finally bought a nitrate test kit and found that my nitrates were off the scale (I previously only tested for pH, ammonia, and nitrites).

I did 25% water changes (vacuuming the gravel) for 3 days straight. (Side Note: After the water changes my cherry barbs got very frisky, but then they would start to mope around again like before) The nitrates go down to around 10-20ppm. Within about 4 hours the levels go to above 20ppm. After a day the levels are right back where they were before. If this means something is decaying in there, I can't find it. I took out my driftwood and vacuumed everything. Is something decaying the only possibility? (Tap Water Nitrates/Nitrites = Undetectable)

I decided to clean the filter box and ran the media under tap water. OOPS! Must have killed some of the bacteria, because nitrites went to .5 for about 4 days, then went back down to nothing. After the nitrites had been up for 2 days the ammonia went up to .5. Now the ammonia is down to .25. Did I just mini-cycle? If the nitrite levels returned to 0, should my nitrifying bacteria be OK

Also, after the water changes I noticed the pH went down to below 6. I added some baking soda to add to my non-existant KH. The pH went up to 6.8 within an hour. OOPS! Everyone came out OK though. WHEW! (Tap Water pH = 7.8)

I made a 10% partial change since the last 25% (last 25% was 4 days ago). Same nitrate problem.

If you made it this far, can you give me any pointers?

My tank has:

1 - 2" Angel
2 - 2" Cherry Barbs
3 - 1" Cherry Barbs
4 - 2" Mollies
1 - 1" Silver Tipped Tetra
1 - 5" Pleco (I've been cleaning up after him regularly [nasty devil])

Various real plants

Thanks!

 

[tttnjfttt]

I'm not the most experienced person here, but as far as I can tell, it sounds like you are doing everything right. Be sure to keep up with the daily water changes until the ammonia is also back at zero. If you do need to clean your filter, which sometimes does actually need to happen, be sure to use old tank water OR dechlorinated water. Either will work fine, its just the chlorine that kills bacteria.

I'm not honestly sure what is causing the nitrates, so hopefully someone else can answer that one. Thats one thing I meant to buy a test kit for yesterday, then totally forgot.

Welcome to the board!!!

 

[sinistral]

Hi Graft,

What's the highest level of nitrate on your test kit?

Did I just mini-cycle? If the nitrite levels returned to 0, should my nitrifying bacteria be OK

I would suggest that yes, you did mini-cycle. It's likely (as you probably know) that either the force of rinsing the sponge or the chlorine-compounds in the tap water caused a bacterial loss or die-off. From your subsequent readings it sounds the colonies are reestablishing themselves, so they ought to be fine down the road.

The nitrates go down to around 10-20ppm. Within about 4 hours the levels go to above 20ppm. After a day the levels are right back where they were before. If this means something is decaying in there, I can't find it. I took out my driftwood and vacuumed everything. Is something decaying the only possibility?

and

Also, after the water changes I noticed the pH went down to below 6. I added some baking soda to add to my non-existant KH. The pH went up to 6.8 within an hour. OOPS! Everyone came out OK though. WHEW! (Tap Water pH = 7.0)

What was your pH running before the water changes?

The other possibility is the dreaded "being overstocked" (dun dun dunn). I believe this is a likely possibility as having nitrates produced that quickly plus having pH downward drift (assuming water changes didn't cause the pH drift, seems unlikely given your tapwater's pH) indicate overstocking. The metabolic process of fish over time tend to cause that downward pH trend-- there are other causes, but given what you've described, I'd wager that this is the most likely possibility.

Overstocking isn't just caused by having too many/too large fish. Another problem is underfiltration. What kind of filter are you running? It may be beneficial to increase the amount of filtration by either upgrading your filter or adding another filter of a different type to your system.

Another tactic you could try would be adding lots and lots of plants. Plants utilize both ammonia and nitrates as food sources (not nitrites though). Being heavily planted would probably help with the nitrate problem. Unfortunately, plecos and plants don't tend to go together, as plecos will uproot plants accidentally as they swim around and root around in the substrate.

As you discovered, I wouldn't be too hasty about trying to adjust pH. Glad to hear the fish are well though.

Otherwise I have to commend you (not that I'm in any position to do that) for your comprehensive post including all of your water parameters (both tank and tap), and also documenting everything you've tried so far. You do seem quite knowledgeable about fish HTH~

 

[Graft]

Thanks a TON for the replies!

tttnjfttt: Thanks for the support. I'll definitely not use tap water on the filter again. I've got to keep the little buggers happy! And I hope your luckier than I was. I had to buy my nitrate test kit online. I guess none of the stores around here want customers to know everything about their water. More deaths = More business.

sinistral: You chimed in right as I was about to reply to tttnjfttt. My thoughts can be expressed with this smiley guy:

What's the highest level of nitrate on your test kit?

My test goes up to 180. I use the Aquarium Pharmaceuticals brand. Their nitrate kit is a workout in itself!

What was your pH running before the water changes?

My pH before the changes has been very "consistant". The tank started at around 6.6 and has gone down to 6.2-6.3 over the period of 10 months. It has been at around 6.2-6.3 for the past couple months. I figured it was because of the driftwood.

And I forgot to mention in my first post was that I treated my tank with pH-UP before the first 25%. Only half the daily dosage though (should have raised the pH by .1 theoretically), since I used almost all of it up during the cycling. I read that can cause the pH to become unstable, but:

pH-UP + 22.3 Gallons @ stable 6.2 + 7.5 Gallons @ 7.8 = Crash to below 6?

Did I fail maths class or does that not add up?

The other possibility is the dreaded "being overstocked" (dun dun dunn).

"dun dun dun" is correct. I almost soiled myself when I saw that. I really REALLY don't want to believe that my tank is overstocked, because I want some friends for my lonely Silver-Tip.

My filter moves quite a bit of water. A danio swims in the current all day, chasing anything that comes near him. I thought I was set up with that. It's a "sits on the back of the tank with a tube that goes in the water and the water goes through the media and biowheel" filter "Suitable for up to 65 gallon tanks". I hope that's enough.

Another tactic you could try would be adding lots and lots of plants.

I'm way ahead of you on that one. Had Red Ludwigia prior to 2 weeks ago, but now have a plethera of low light plants (I went plant crazy about 2 weeks ago). There is basically no room on the floor to add new plants, unless the new plant doesn't like light. There have been alot of leaves dropped, but they only stay free floating for 12 hours max. Plus I pick the dying leaves before they have a chance to start to foul the water. I'm pretty sure the plants weren't the problem, so I didn't include them in my post.

Any guesses on the pH? Does any of this information keep you away from the final verdict, "Being Overstocked" (That's like a jail sentence).

Thanks again for the replies!

 

[rdd1952]

I'm totally at a loss as to why your nitrates are shooting up that much unless it's from over feeding (decaying food) or decaying leaves form the plants. Trust me, they all don't float to the top. I have a heavily planted 75 gallon myself. That is one of the drawbacks to planted tanks: you can't do a good gravel vac and so dead/loose leaves rot and decay. With high nitrates, you should have a major algae problem unless the pleco is keeping it in check. High nitrates are one of the top causes of algae. They generally shouldn't rise much at all, especially over that short of a time frame.

You are overstocked but that's pretty much because of the pleco although you mention a danio swimming in the current but he isn't in the list of fish you posted in your first post. Did you leave some out? You will have to re-home the pleco before long. You should see if you can return him and maybe get acouple dwarf plecos of some type (bristlenose maybe). And as you said, the tetra needs at least 5 buddies since they are schooling fish.

I would get totally away from the pH chemicals. If your regular pH is running 6.2 or 6.3, that is perfect for all of the fish you have except maybe the mollies who prefer brackish water with a little salt thus a slightly higher pH. If you want to raise it a little to accommodate the driftwood, put about a teaspoon full of crushed coral in your filter pack. That will help raise the pH slightly and will still keep it stable.

It sounds like your filter is fine. You have a 37 gallon tank so your filter should be rated for at least 200 gph. If it says it's for up to 65 gallons, then it's probably closer to 325+ gph. Since you are overfiltered, being a little overstocked isn't a problem.

 

[3fsh]

#1. DO NOT use pH down or pH up on your water. It will mess with your water parameters and do a lot of weird stuff. Your best bet is to buy fish that are comfortable with the pH of your water.

#2. It is my opinion that the pleco is 99% of where the high nitrates are coming from. The filter may be able to keep up with getting rid of the ammonia in the water, but it can't do anything about the Nitrates which are building up like crazy.....

#3. ...so quickly, in fact, that your plants can't keep up with it because they probably don't have good gravel to root in or good light to grow them or a very low oxygen content to keep algae from growing on them and to help them grow as well. Plants are great for getting rid of Nitrates as long as they are cared for properly. Leaves should not be falling off of your plants... that is a sign that they are dying. What do you have them planted in? It's best to have them in an iron enriched substrate such as Flourite. I have my plants in a 3/4 flourite 1/4 gravel mixture, and they seem to be doing well. Check their roots... are they nice and firm and long, or soft and stringy and gunky? They may be rotting and making your problem even worse. How much lighting do you have over the tank? IMO, it is definitely worth it to invest in a good set of compact flourescent lights. Last, but not least, how much oxygen is getting put into the tank? Do you have any air stones running? Is the filter creating a lot of splahes and bubbles? Plants hate oxygen because it is what they are supposed to make. They need an abundance of Co2 (what the fish give off when they "exhale") in order to be healthy and happy.

Hope that helps! Please ask if you are unclear about something I have said.

 

[Graft]

Oh yeah. I forgot to mention my:

2 - 2" danios

There were more, but they dwindled away. That's it. I counted my fish just now and that's it.

Yeah, my pleco is getting bigger. He started in a 10 Gallon till about 3". He then graduated to the 37 Gallon. He'll be going to a 90+ Gallon once I get a good foothold on proper fishkeeping and buy a new tank. I can't part with him. I got him when he was less than 1". I knew he'd get big and I want to keep him for the long haul.

I definitely want to get a smaller pleco in the future for this tank and brittlenose looks like they're the way to go. Are there any other more colorful dwarfs?

If you want to raise it a little to accommodate the driftwood, put about a teaspoon full of crushed coral in your filter pack.

I was under the impression that you don't want to add crushed coral to a freshwater tank (conflicting posts on this forum). I needed to raise my KH so I added baking soda. Is that not a good idea?

I agree that vacuuming has become a problem with all the dwarf sag, but I just put both my arms in the water and stir up the gravel and capture it that way. It seems to get most of it out.

Thanks for replying!

 

[Graft]

#1. DO NOT use pH down or pH up on your water. It will mess with your water parameters and do a lot of weird stuff. Your best bet is to buy fish that are comfortable with the pH of your water.

Done and DONE!

#2. It is my opinion that the pleco is 99% of where the high nitrates are coming from. The filter may be able to keep up with getting rid of the ammonia in the water, but it can't do anything about the Nitrates which are building up like crazy.....

That's not what I want to hear, 3fish. C'mon, lie to me. Tell me it will all be OK, the pleco can stay for a while. I'm guessing I've got a month or two before I buy a bigger tank and I want this problem cleared (the sooner the better). I hope you're wrong, but I'm guessing you're right.

#3. ...so quickly, in fact, that your plants can't keep up with it because they probably don't have good gravel to root in or good light to grow them or a very low oxygen content to keep algae from growing on them and to help them grow as well. Plants are great for getting rid of Nitrates as long as they are cared for properly. Leaves should not be falling off of your plants... that is a sign that they are dying. What do you have them planted in? It's best to have them in an iron enriched substrate such as Flourite. I have my plants in a 3/4 flourite 1/4 gravel mixture, and they seem to be doing well. Check their roots... are they nice and firm and long, or soft and stringy and gunky? They may be rotting and making your problem even worse. How much lighting do you have over the tank? IMO, it is definitely worth it to invest in a good set of compact flourescent lights. Last, but not least, how much oxygen is getting put into the tank? Do you have any air stones running? Is the filter creating a lot of splahes and bubbles? Plants hate oxygen because it is what they are supposed to make. They need an abundance of Co2 (what the fish give off when they "exhale") in order to be healthy and happy.

The only plants loosing leaves are new Hygrophilia and an Amazon Sword. The Hygrophilia was a little battered looking when I got it, but the new growth seems to be great looking. It was marked as low light, but I think that might not be the case, since it's a little stringy. The Amazon Sword should have been OK, since it's plantlets have taken root in 100% flourite and I feed them fertilizer every week. A little lower than the lowest recommended dose (because of my afore mentioned nitrate problem).

My tank could difinitely use better lighting, but I am unsure if I can create a good looking hood like the one I have now. Its a looks thing. If I had a canopy, it could hide it, but a canopy would look weird on such a small tank. It was my poor lighting that prompted me to buy all (or mostly) low light plants.

I don't use air stones and my fish never have problems breathing. Once I had my pH and KH in check, I set up a DIY CO2 system. It's been running, but I am unsure if it is having any affect. Smells like some good bread though. Makes me hungry.

Thansk for the advice 3fish!

 

[sinistral]

I don't use air stones and my fish never have problems breathing. Once I had my pH and KH in check, I set up a DIY CO2 system. It's been running, but I am unsure if it is having any affect. Smells like some good bread though. Makes me hungry.

Ah HA!

That's the source of the low pH. You've also mentioned that your kH is low-- so the water has limited buffering capacity to protect against rapid pH changes. If you added pH up (which is sodium hydroxide, NaOH) to a low buffer solution like your tap water and then added a significant quantity (25%) of that to a low buffered solution like your tank, it's likely that you used up most of the buffering capacity of the tank in one fell swoop. The problem here is that the CO2 drives pH down, so even if the added water had a relatively high pH, the combination of CO2 and low buffered water caused the pH crash. Hopefully that made sense... If you remember doing titration curve experiments in general chemistry, hopefully that sounds familiar...

What other plants do you have? Hygro should help as it's a fast growing plant that competes with algae for nutrients and also uses quite a bit of nitrate. It will grow in low light but 2 watts per gallon would probably be a lot better.

Another cause of high nitrates of course is overfeeding... how much are you feeding the fish now?

 

[Graft]

Well, sinistral, I got C's in CHEM I & II (because I always "overslept"). However the added baking soda brought my KH to 4 degrees. All water changes since then have added soda to them to make them 4 degrees as well. Strangely enough, after about 3 days the KH went down to 3 degrees (CO2 was only active for about a day). What the heck? Guess the driftwood is working its magic? Or is CO2 that acidic?

I feed my fish less than I have in the past. Around 3 small pinches (I know that a pinch is relative, but I don't break out the teaspoon). No food ever makes it further than 1/2 way down the tank. I feed the pleco once every 2-3 days now. Just to keep his over-active bowels from dirtying up the tank.

I've got about 7 stalks of Red Ludwigia (2 are almost at the top of the tank), 7 Apogs that are now regrowing (1 Aponogeton Natans with 4 babies, not sure what the rest are, store bought bulbs - very nice though), around 14 Dwarf Sags, 2 nana Anubias, 1 Anubias barteri, 3 amazon swordlets (i heard they could be grown under lower light conditions), a row of Java Fern, a bunch of Bolbitus heudelotii, 1 Red Tiger Lotus, 1 Bronze Wendtii, and 1 Cryptocoryne crispatula.

The Aponos are fast growers, but I'm guessing they don't hog alot of nitrate like hornwort. Do you or anyone know about how well Java Moss gets rid of nitrate. I have a HUGE chunk in my 10 gallon and I was thinking about using it as a nitrate sponge until I can get the pleco into a bigger tank.

Thanks for the reply, sinistral. I'm guessing most of this stuff is irrelevant, I'm just typing to see myself of the internet!

 

[sinistral]

There is a way to calculate the concentration of CO2 in your tank from a chart, found here.

If your pH is about 6.2 and your kH is about 3 degrees, then the concentration of CO2 is about 56 ppm. I realize these values may not reflect what's going on in your tank right now, as the addition of CO2 and the adjustment of your kH and pH with baking soda has been an ongoing process. Anyways, the recommended range for CO2 concentration is about 10-20 ppm. It's a balancing act between CO2 and kH to get things into real balance.

Is your CO2 rig DIY? Yes, CO2 is that acidic that it could use up that much buffer over the course of a day. I'm not sure how the driftwood you have will affect the tank pH. I suggest this because if you got store bought driftwood that has had most or all of the acidic tannins leached out of it already it shouldn't affect pH too much.

You must be doing pretty well light-wise if your Ludwigia is intensely red and growing. Sounds like you have a nice mix of plants. If you have a photo I hope you'll post it in the Member's Aquarium Photos section Java moss grows so well that I can only imagine that it soaks up nitrates; however, I can't say I know this for sure.

If you are overfeeding you may find out sooner or later as you might either experience a snail population boom (if you have snails) or an algae outbreak (with excess nitrates and phosphates from metabolised fish food). If you have neither then my hat's off to you How many times per day are you feeding?

 

[Graft]

Oh MAN, I hope I don't kill my fish! I made up a new batch of yeast/sugar last night and threw it in today, since my other was just a test and it smells like moonshine. It's bubbling good and the pH has gone down .4 since this morning. My KH is now at 1 degree and my pH is at 6.4. That translates to about 12 ppm according to the chart.

This is turning out to be a nightmare! I'm not sure if baking soda is good for the fish seeing as how it has sodium in it, but it's the only thing that I have handy. I'm buffering in small increments right now. I don't want a huge pH shift like last week.

The plants are doing fine and java moss is awesome (just a little unruley), and I don't have any pictures, although I plan on taking some soon. Hopefully with live fish!

I'm stumped on how people keep their CO2 systems from using up all the buffers. Do they buffer with bicarbonate regularly? I'm a searchin', but I ain't a findin'. It might be time for a new thread...

Oh, and I feed them once a day now. Used to feed them twice a day, once in the morning (6am - WAY too early if you ask me) and once at night (8pm - Lights off at 9pm), but with my problems I'm cutting back.

Boy do I love chemistry!

Edit: Oh heck. For now I will just raise the bubblers to not allow the CO2 to disolve as much (I hope my reasoning is correct). I don't want to make a bad situation worse.

 

[sinistral]

I think you're moving in the right direction-- trying to juggle different elements (CO2, baking soda) to work out a good balance in the tank. On the krib website George Booth has an article about a system he worked out (have to warn you, it's rather complicated) for adjusting kH, pH, CO2 flow, etc etc. I'll see if I can find it.

 

[Graft]

Cool!

I found the information and it says that they use crushed coral with a little baking soda. rdd1952 said to use crushed coral to balance out the pH. From what I've read, crushed coral raises GH and KH. My GH is 14 degrees right now, so I really don't want to use that.

I've almost balanced out my KH. Some baking soda last night, some this morning, some at lunch, and some a little while ago has raised the KH to around 3 degrees and pH to 6.6. So my CO2 should be around 20ppm according to the chart.

I'll probably invest in a RO filter, but at $130 at the cheapest, I might wait until I get another tank. That should give me an excuse to buy RO.

Thanks for all the help sinistral. And everyone else. This forum rocks!

---------------------------------------------

Ammonia - Somewhere around 0 - .25
Nitrite - 0
Nitrate - Rose to the low side of 20 - 40 (much better than 80 - 160)
pH - 6.6
KH - 3
GH - 14

Hopefully I can keep these numbers better in the future.

 

[Graft]

Just figured I'd put an end this thread/nightmare.

After daily water changes for a week, I finally got the nitrate to only rise to 20. After one week of two water changes and two weeks of only weekly water changes the nitrate levels are at 10 (I'm guessing this is due to my abundance of plants).

Also, I have been adding a pinch of baking soda weekly to the water for the past two weeks to keep the KH around 4-5 (the CO2 is around 12ppm according to the charts).

Thanks for all the help, people. You guys rock!