The QT Biofilter Catch 22

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ariellemermaid

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Since starting reefing about 7 months back I’ve read every thread I could find on QT, copper, cycling, and just about everything else. It seems there’s a bit of a catch 22 when it comes to this topic.

Summary of my take away points combining different threads:
1) Fish die quickly without a biofilter or extremely frequent water changes.
2) Copper damages the biofilter
3) In the presence of copper, no ammonia test can be relied on

So, a QT tank likely has a poor biofilter even with a seeded sponge. Copper damages it to an unknown degree, and you can’t actually measure ammonia accurately with copper yet the fish are supposed to survive those conditions for at least 30 days.

This leads me to my current conundrum. My next QT had a good biofilter and I made it through with some prime and weekly water changes. But on this round I had some sick fish and a bigger fish and ultimately 2 weeks of neoplex/metroplex/furan-2 wiped out my biofilter. After a huge water change and carbon I added a sponge from my rock solid DT (6 months old plus a bags worth of cycled media). Results haven’t been ideal; I’m stuck at the ammonia/nitrite stage with q3 day water changes, but it seems to be improving. Definitely didn’t get an “instant cycled” tank.

I want to start copper as soon as ammonia stays down but I don’t trust this tank, and adding copper could set back biofilter gains. I feel like starting copper without being able to monitor ammonia is risky. Sure dosing prime throughout and picking a random water change interval could work ok, but I definitely don’t want to be doing water changes every few days during copper with all the measurement and redosing headaches.

Any suggestions to deal with this set of contradictory problems?

Note:
Now before anyone suggests the Seachem ammonia badge let me just stop you right there. I have 3. On my first ever QT I tried to fish cycle 2 clowns with Turbostart. Before a week was up, the fish were dead. Ammonia (API) was ~0.25-0.5 and the badge was still solid yellow. I never used Prime so it’s not about bound vs. unbound. (Yes, mistakes were made- I should have used Prime and should have tested daily with a proper kit and not trusted the badge). After that I decided to cycle my empty DT with ammonia directly in addition to the 2 QT’s. I would add ammonia up to 1.0 and the badges would barely start to change from yellow, certainly nowhere near the 0.5 high alert blue color. No prime had ever touched the tanks. Suffice it to say, I consider the badges a decoration, not something to keep fish alive.
 
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SDK

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The broad answer to your question is that if you are using copper, it should be for a specific reason. If so, then its going to be the lesser of two evils.

When I have to use copper, I go back to my killifish breeding roots, and use scrupulous cleaning to deal with organics. There really is no shortcut, especially considering that I would already be dealing with a sick, stressed fish at this point.

I mix enough fresh saltwater to get me through a week and keep the tank furnishings minimal. Every evening I use a piece of rigid airline tubing attached to a piece of flexible airline tubing and carefully vacuum the bottom completely clean. You can do this with the small tubing and only remove a gallon or two. Then replace with fresh saltwater and adjust the copper.

With a Hanna copper test kit, you can do the whole routine in 15 to 20 minutes, and you won't be stressing the fish out with big water changes and dissolved organics building up. You technically don't even need a biofilter with this routine, although its obviously good to have a sponge running in tandem.

In your post you mention not wanting to do water changes or testing even every "few" days. My advice would be to rethink that position. It's just a temporary chore and well worth the extra effort versus losing a fish...
 
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ariellemermaid

ariellemermaid

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That’s an idea; much smaller more frequent water changes. This QT has been weird; two small cardinals and a small yellow tang. Thing is...after 2 weeks I have yet to find any poop in the tank! Still have ammonia I guess from respiration and urine but I have no idea where the poop is going so there hasn’t actually been anything to vacuum up.

We’ve been following the Humblefish philosophy of ich eradication. Every fish gets treated for ich, treat with antibiotics only on an as-needed basis.
 

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Are the fish eating? There should be feces and they can stick to a sponge filter with a strong air pump. You can try pushing the Vacuum onto the sponge or giving it a little squeeze into the bucket of water you siphon. You may be surprised at how much junk comes out.

Of greater concern than the poop is any uneaten food. That will degrade the water much faster than the poop will.
 
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ariellemermaid

ariellemermaid

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Are the fish eating? There should be feces and they can stick to a sponge filter with a strong air pump. You can try pushing the Vacuum onto the sponge or giving it a little squeeze into the bucket of water you siphon. You may be surprised at how much junk comes out.

Of greater concern than the poop is any uneaten food. That will degrade the water much faster than the poop will.
I’m not too worried about the poop; they’re eating great! So either someone has a little coprophagia thing going on or I suppose maybe the flow is so strong it’s getting suspended and taken into the filter. Strange though because with past QT’s I would find it very clearly on the bare bottom.
 
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