Going Fishless in Established Acro Tank - mistake?

jjencek · Mar 14, 2023

I have a 5 year old all acro tank. 6 months ago I decided to go without fish or anything else I needed to feed. I figured I could dose all the SPS needed. I think it was wrong. They grow fine, but the colors have suffered. Here is all I do for them:

1. 10% water every 2 weeks (Red Sea Salt)
2. Dose Nitrate (about 4 ppm)
3. Dosing Phosphate ( about 0.050 ppm)
4. Dosing Red Sea Reef Nutrition AB+ (amino and more)
5. Dosing Red Sea Coral Colors A,B,C,D (minor elements)
6. Dosing Alkalinity (8.0-8.3)
7. Dosing Calcium ( about 430)

Has anybody done the above with success? I am thinking about returning a few fish and some peppermint shrimp back in. I think fish does add something I don't know about.

chipchipmofo · Mar 14, 2023

I think you need Ammonia from fish poop/pee for acros to thrive.
It would be much easier to just add some fish back

@Charlie’s Frags

jjencek · Mar 14, 2023

chipchipmofo said:
I think you need Ammonia from fish poop/pee for acros to thrive.
It would be much easier to just add some fish back

@Charlie’s Frags

I believe you might be right. If it is just Ammonia, I can also dose that without fish. But who knows...

The Opinionated Reefer · Mar 14, 2023

Stupid idea to have no fish in a reef tank imo

homer1475 · Mar 14, 2023

Ammonia #1 your missing without fish. Coral metabolize ammonia much easier, and actually prefer it over then residual nitrates left over from the cycling process.

Not just poop and pee, but just respiration by the fish creates ammonia.

chipchipmofo · Mar 14, 2023

So the easiest solution for you: Add some fish

jackson6745 · Mar 14, 2023

I did fishless years ago. SPS did ok but everything was pale. It looks very cool in a zeovit type of way on some pieces, but overall I don't like the look. Growth, color, PE, and overall vibrance was better in thanks that I fed well + filtered well. Curious to see how a fishless tank does with the addition of No3. I didn't dose nitrate when I went fishless.

jjencek · Mar 14, 2023

jackson6745 said:
I did fishless years ago. SPS did ok but everything was pale. It looks very cool in a zeovit type of way on some pieces, but overall I don't like the look. Growth, color, PE, and overall vibrance was better in thanks that I fed well + filtered well. Curious to see how a fishless tank does with the addition of No3. I didn't dose nitrate when I went fishless.

Playing with just the nitrate and phosphate will change the colors. I can tell when I overdo it by them turning brown. And when I underdo it, they go pale. I never got the bright colors the way they were when I had fish in the tank. So as other wrote - I will PUT THE FISH BACK and report back in a couple of months.

chipchipmofo · Mar 14, 2023

jjencek said:
Playing with just the nitrate and phosphate will change the colors. I can tell when I overdo it by them turning brown. And when I underdo it, they go pale. I never got the bright colors the way they were when I had fish in the tank. So as other wrote - I will PUT THE FISH BACK and report back in a couple of months.

Yeah please update this thread. Its a very interesting topic though.
Maybe do some Before and After pics?

homer1475 · Mar 14, 2023

Even most frag tanks have a couple utilitarian fish in them.

Randy Holmes-Farley · Mar 14, 2023

IMO, there's not much evidence that I have seen that suggests nitrate and/or amino acids is not adequate for corals, even if ammonia may be a preferred source to nitrate. There will be some ammonia from the amino acid degradation.

Dosing ammonia is not hard and there are threads on it, if you want to go that route.

Dennis Cartier · Mar 14, 2023

I believe Tropic Marin has a big SPS tank with no fish. They dose their NP Bacto Balance as the nutrition source apparently. The tank in question is visible and discussed in one of their videos, but unfortunately, only in German.

Enderg60 · Mar 14, 2023

My coral QT has no fish and runs fine. But I do have shrimp in there and I drop a few pellets in with a auto feeder once a day to keep the nutrients measurable.

jjencek · Mar 14, 2023

Dennis Cartier said:
I believe Tropic Marin has a big SPS tank with no fish. They dose their NP Bacto Balance as the nutrition source apparently. The tank in question is visible and discussed in one of their videos, but unfortunately, only in German.

I thought Bacto Balance is a carbon dosing method to lower nutrients. I just read their description and I am confused ... it seems to do both ... lower the nutrients, but not to zero amount ... and it then keeps them in balance. Am I understanding it right?

Randy Holmes-Farley · Mar 14, 2023

jjencek said:
I thought Bacto Balance is a carbon dosing method to lower nutrients. I just read their description and I am confused ... it seems to do both ... lower the nutrients, but not to zero amount ... and it then keeps them in balance. Am I understanding it right?

It's seeming intent is to reduce nitrate and phosphate with organic carbon dosing, while adding N and P in organic forms.

delv2323 · Mar 14, 2023

If you are worried why not just feed the tank flake or whatever and let it breakdown. The nutrient pathway will be the same regardless of it it gets eaten by pods, fish, sea turtles, or mermaids.