Fallow, Nutrient Ratios and Biopellets

DanielJameS · Mar 26, 2018

Hey all,

So I’m Fallow again (2nd time on this tank) and am working on my new tank in the process. The last time I went Fallow, despite feeding corals and broadcast feeding the tank, I suffered a major nutrient imbalance that took a long time to correct. I had a decent bio load and kept my nitrates a little higher with my LPS/Softies thriving. Upon the first week of removing the fish the corals never looked better. I assume that’s an indication that slightly lower nitrates (maybe around 10ppm) might be a sweet spot but now (about 3 weeks in) my corals are starting to suffer. Nitrates have dropped pretty quickly down to 2-5ppm and I’ve tried to dose nitrates as I have some pre made stump remover nitrate solution made up. Ive taken my skimmer offline but my concern now is my biopellets. It took them a LONG time to kick in and I was hoping I could keep them running till I get the new tank up. Now I’m concerned that they will strip everything clean but phosphates will remain higher and I’ll experience another nutrient imbalance.

What have those of you that have had success with fishless coral systems done to keep your corals thriving nutrient wise? Should I run the system bare bones, maybe just some polyflter, no other filtration and feed the tank more? I’ve tried to dose some aminos via some reef plus to get some extra into the water but I have another 7-8 weeks to go and am worried about losing a lot of what I planned to stock the new tank with.

saltyfilmfolks · Mar 26, 2018

Imbalance or a limitation (a true zero)? Most of the balance thing had been debunked.

What probs Are you seeing problems with the coral or just test numbers.

I’ve had my coral qt up for a couple years now and really have only ever just ghost fed it with “left overs”. It was pretty tough at first to find the right amount.

Personally , if you want to keep the pellets I kinda feel like you should feed close the same amount you did with fish in the system.

Randy Holmes-Farley · Mar 26, 2018

It's certainly a complication to leave the pellets in place in a fallow system. If you want to, I'd probably measure and dose.

DanielJameS · Mar 27, 2018

Thanks All, The main thing I’m seeing is corals suffering, i tend to rely on the eye test first then follow up with testing. The last time I went Fallow I experienced a similar issue. 2-3 weeks after removing all the fish, I started to experience issues with hair algae and/or cyano. I noticed a significant (quick) decline in nitrates once removing that bio load, so I always assumed the phosphates present started to outweigh the nitrates and that’s where the hair algae started to form. Prior to the fish being out of the tank I’d say my NO3 was around 15ppm and has quickly declined to <5 maybe lower. Hair algae is quickly growing in patchy specific areas, and never had any HA with fish in the tank. I’ve removed all major stripping type filtration like carbon and polyfilter, the only thing I’m still running are the bio pellets. I’m just wondering if I should let those run as normal. I am going to continue to feed all types of food I would feed the fish (LRS, cyclopeeze etc) as I still have an anemone and a couple shrimp in the tank.

I just want to gain some knowledge as to what the best approach is for Fallow. I’m going to be setting up a QT for corals and I feel like that will be fine if stable, I think it’s the quick change in bioload that may cause the issue. My corals have been “used to” 12 fish in the tank with them nutrient wise for 8-9 months and all of a sudden boom...gone.