Canister filter woes so soon?

[Maswired]

My tank is 81 days old. I have had zero readings for ammonia, nitrites, nitrates since day 30 or so. I started the tank with half live rock, half base rock, live sand that originated in another tank, that went through a major cycle. My tank has been almost rock stable for the past 80 days with minor fluctuations.

I have added, over the course of a month and a half, one frag of pulsing xenia, one small purple mushroom, one small frag of sympodium and 13 days ago, a small frag of frogspawn. I also added 2 juvenile (size of your thumb) ocell. clownfish at the same time as the frogspawn. I have ten hermit crabs that have been in the tank for 40 days or so, and a dozen cerith snails, 4 nerite snails. I have a bunch of cheato in the back, behind the rocks, and a large in tank breeder box stuffed with ulva and small rock frags.

I am running a 90L (25? gal) red sea berlin airlift protein skimmer, and recently switched from an HOB filter rated for 60-80 gal to a very quiet Eheim 2213 canister filter. I put purigen in the canister today, after taking readings. I clean the canister weekly and replace the water polishing pads weekly. I do not have a sump, a refug, or any other add ons. I am overly obsessive about the tank and keep a close eye on it. I test water parameters daily.

Salinty: 1.024
PH 8.2 (it has fluctuated between 8.0 and 8.2 after adding frogspawn)
Ammonia 0
Nitrites 0-.0125 (not quiet the blue of .25 and definitely not 0)
Nitrates 0
Calcium 400 ppm after dosing (it got as low as 360 ppm last week)
Magnesium is approx 1350ppm
phosphates are 0.00 - .04 ( Red Sea Phosphate Pro)

I use Instant Ocean regular (not reef)

I feed the fish and hermits 1 cube of either mysis, Formula One, or SF Brand Saltwater Multipack 4 types food, per day, along with a late evening pinch of Omega One Marine micro pellets. A small pinch means the smallest amount I can pinch between my fingers.

I recently began dosing a 2 part B-ionic alk/cal system daily, as my magnesium and calcium levels started fluctuating. My alk has risen to 11, where it had been 8-9 consistently for months. The frogspawn seems to like calcium, as the levels began dropping about 4ppm per day after I added it. I went three weeks between adding the mushroom, xenia, and sympodium, so I was able to watch the calcium/magnesium levels. The frogspawn sucks calcium. I have been dosing the 2 parts for four days now.

My issue is the rise of Nitrites. I have consistently had zero nitrites, almost from day one. My nitrates spiked during the first month and then disappeared. I had swings of Nitrates early on, but then everything settled. I have had no ammonia after the first two weeks.

So why are my nitrites detectable? I tested yesterday and today and the reading is between zero and .25 ppm. There isn't a LOT, but I am picking them up now, where they have been undetectable before. I am using an API test kit that is about three weeks old. Am I looking at a new cycle? Could the canister filter be adding nitrites, but nothing else to my tank? I rinse the compartments and the pads with my RO filtered water that is plumbed through my kitchen sink. Am I contaminating the inside components of the filter and causing mini-cycles inside the canister and that is adding nitrites? There are bioballs in the bottom of the canister, then a blue sponge, then more smaller bioballs, the white polisher pad, the carbon pad, then purigen packet (From bottom to top).

I do weekly 20% water changes. I did two water changes last week because I over dosed on straight calcium, and wanted to correct that. I had snow and the water changes took care of that. I mix my water the day before, but optimally, two or three days before. I run a power head and a heater in the bucket with my fresh mixed water. I stopped dosing fluval magnesium and the calcium last week, as I could not determine the right balance, and feared throwing off my chemistry. I was dosing once a week with those. After last weeks water changes, I let the system ride without dosing until this week. My calcium dropped to 360 ppm and my magnesium dropped to 1200 ppm. Thank frogspawn! I started dosing the two part system this week and things are getting back to where they were before.

I recently had to move a large rock, and repositioned it so that the part that had been undergravel/sand, was exposed. It quickly turned brown with the algae bloom that was going on at that time. I am still having algae blooms periodically. I went from bright green to now brown. I have small patches of coralline (bright purple) and an encrusting bright/light green algae that is slowly taking over my rocks. No baddies - cyno, aiptasia, etc. that I can find. No black spots of fungi. I think this is part of the tank maturing. Could the algae bloom also contribute to the nitrites? Have I overstocked too soon, or otherwise caused a delay in a true tank cycle?

I am in need of wisdom on this one. I have no clue what is going on. Any advise is much appreciated!

 

[Maswired]

Picture of my 20 gal

Picture of my 20 gal

Here is a picture of the 20H

 

[Maswired]

I am doing daily water changes of 20% until the nitrites resolve. There is no ammonia, no nitrates, so if I am over feeding, the water changes will help and there will be an immediate effect. I wonder if the biomedia is at the root of this?

 

[IDreamOReefin]

Could it be that the new bioload has added new ammonia that in turn produced new nitries? And said nitrites have yet to be converted into nitrates?

 

[Maswired]

I would think so, but I have no indication of ammonia or nitrates. Can Nitrites just appear by themselves? I am confused! I have been checking parameters closely because if the frogspawn and the drop in calcium and alk and magnesium, so daily, there has been no ammonia. So the ammonia has to be there, is just being consumed, that develops into nitrites, and then not enough nitrates to consume nitrites, so a build up of nitrites. I would then think that there is too much ulva and cheato in the tank, consuming nitrates that need to be left in there to consume nitrites. Am I close to understanding? I could just take out the ulva and see if that helps? Weirdness. Thanks for your thoughts! It might have solved it?

 

[gone fishin]

Nitrites just don't appear. They are the byproduct of ammonia breakdown.

Personally since you have a skimmer I would ditch the canister and see if that clears things up. Just my 2 cents worth.

 

[NS Mike D]

I would think so, but I have no indication of ammonia or nitrates. Can Nitrites just appear by themselves? I am confused! I have been checking parameters closely because if the frogspawn and the drop in calcium and alk and magnesium, so daily, there has been no ammonia. So the ammonia has to be there, is just being consumed, that develops into nitrites, and then not enough nitrates to consume nitrites, so a build up of nitrites. I would then think that there is too much ulva and cheato in the tank, consuming nitrates that need to be left in there to consume nitrites. Am I close to understanding? I could just take out the ulva and see if that helps? Weirdness. Thanks for your thoughts! It might have solved it?

ammonia>nitrites>nitrates

the bacteria that converts ammonia to nitrites is different than the bacteria that converts nitrites to nitrates. I just went through this with my new tank. last week, after adding some life to the tank, the nitrites spiked to 2ppm with 0ppm nitrates and ammonia. Today they are both zero. I presume that it took a week for the second set of bacteria to multiply with the new nitrites to feed them.



Re Water Changes:

Also, when I was researching my water chemistry parameters, I came across a good write-up by Randy Holmes-farley of reef keeping. Here is what he said about nitrites. If I read him correctly, your daily water changes are not needed.



Aquarists' concerns about nitrite are usually imported from the freshwater hobby. Nitrite is far less toxic in seawater than in freshwater. Fish are typically able to survive in seawater with more than 100 ppm nitrite Until future experiments show substantial nitrite toxicity to reef aquarium inhabitants, nitrite is not an important parameter for reef aquarists to monitor. Tracking nitrite in a new reef aquarium can nevertheless be instructive by showing the biochemical processes that are taking place. In most cases, I do not recommend that aquarists bother to measure nitrite in established aquaria.

 

[Maswired]

Thank you one and all! I am observing my corals, snails, crabs, and two fish and everyone is going about their business as usual. So it does help reading that the nitrites are not as toxic as in freshwater. If I am understanding this, my daily waterchanges might be prolonging the development of the nitrite part of the cycle. Words of wisdom accepted! I lost a crab two weeks ago and thought I had lost one today but that turned out to be a very convincing molt. Thankfully! So no losses, corals open, fish happy, so far so good. I am still nervous about their being nitrites because it does mean a lag in the levels of bacteria. New bioload for two weeks and the bacteria hasn't caught up? So I will continue to monitor closely and do water changes twice a week. I am still suspicious of the canister, but in the absence of a reactor, sump, refugium, etc., chemical and mechanical filter need to happen somewhere in the system. After 180 days or so I was planning on pulling the canister and just going with the skimmer for a week to see, but the system is new and growing, so I am leery of doing that yet. thoughts for future reference on my part. Thanks for everyone advice. I am listening and heeding!

 

[dkeller_nc]

A couple of thoughts about the use and interpretation of test kits from someone with a chemistry background:

Nitrite test kits are tricky; given that your tank has been set-up for nearly 3 months, and presuming that it was cycled with some sort of ammonia source at the beginning of that period (such as a piece of table shrimp, some fish food, etc..), it's really unlikely that you actually have any measurable nitrite in the water. I would change that answer if you'd recently had something significant die, but absent this, I would discontinue the nitrite testing.

It's also not really necessary or helpful to test for ammonia once you've cycled the tank, either, unless you have an event occur that would warrant it (such as the death of a creature with significant mass), a long power outage, or something similar.

With respect to the calcium and alkalinity tests, realize that these have significant uncertainties in the reading that you obtain. Most eriochrome black-based calcium test kits, for example, have a typical uncertainty of about 20 ppm. Similarly, indicator-dye based alkalinity tests that hobbyists use have an uncertainty of at least 0.5 dKH.

Because of these uncertainties, it can be quite difficult to correctly assess and dose alkalinity and calcium supplements based on daily readings. And in a tank as young as yours, it's highly unlikely that one quite small frogspawn coral is consuming significant amounts of calcium and alkalinity. The more likely culprit for changes in your Ca and Alk readings is abiotic precipitation, and the afore-mentioned test uncertainty.

One good way of assessing and adjusting your Ca and Alk supplement amounts is to hold constant the amount that you adding daily, and measure the Ca and Alk after 3 days. If you're seeing a significant drop in Ca and Alk between the 3-day intervals, adjust the daily volume of the supplements upward slightly, and re-test again in 3 days. By the way, any 2-part Ca and Alk supplementation should have the solutions added daily rather than at longer intervals or bolus dosed to try to "correct" a perceived deficiency from a test result.

At the stage that your tank's at, most would simply recommend that you continue your water change schedule; it may not be necessary to dose Ca and Alk supplements with so little calcifying organisms in the tank.