Doing the unthinkable - Vodka Dosing a macro tank

[djkms]

Well my system has been setup over a year now. I have a full on mixed reef and macro algae display tank. My only form of nutrient export are my macro algae's. I have had over 20 different macros in my system and currently have around 15. I have SPS, LPS, softies and everything in between.

For the first six months things where pretty much smooth sailing. Then I had a alkalinity spike and things have been trouble since. I believe the spike crashed my denitrifying bacteria bed. Up until this point I maintained my nitrates around 5ppm and Phosphate around .02-.04. After the alk spike my nitrates shot up around 30ppm and phosphate around .12. This did not make my SPS and chalices very happy and I lost some corals. Before the spike I was feeding 5 times a day, small amounts through a auto feeder and a portion of Rods when I got home. No nutrient issues while feeding. Through massive water changes I brought my nutrients back down to 5ppm NO3 and .02 PO4. At this time I had about 12 fish.

Fast forward a couple more months and my CA reactor got clogged and I over compensated, shooting my ALK up again. Same thing, crash, nutrient spike. This time around I had a lot of other things going on, it was the end of summer and I just kind of let it go (BAD move on my part!). My nitrates topped out at 50-60ppm and PO4 around .16. Yet again I lost more corals and watched my tank really decline, mostly SPS. My LPS, zoas and softies didnt seem to mind though.

I have since been doing massive water changes to bring my nutrients back down. I finally got my trates down to 4ppm and PO4 to .02 and also cut feeding down to 1 time a day sparingly. I now have around 15 fish. Well short of starving my fish my nutrients just keep creeping up about 5-8ppm weekly on nitrates and around .02 weekly on phosphate. I have also been doing 25% water changes weekly to combat this. It has also been my experience that when nitrates reach above 10ppm it seems to stunt nutrient uptake with macros, over-fertilization I think.

Sadly it seams my macros just cant keep up with my load anymore. Remember I went from feeding 5 times a day healthy portions to 1 time a day sparingly. Well this is just not acceptable to me. IMO most reefers starve their fish for nutrient control. Well to help combat this nutrient issue I have started to vodka dose. I hope to get back to feeding my fish 5 times a day while maintaining control over my nutrients. I have been testing daily and keeping a real close eye on everything. I hope to get my nitrate down to 5ppm and PO4 to .02 and use a maintenance dose to keep me around there. I need to keep enough nutrients in the tank so my macros thrive. With careful dosing and testing I am confident it can be done. If my nutrients bottom out for over a week I will stop dosing and explore other avenues. I am always up for a challenge! Wish me luck.

I have been following the guide here:
http://reefkeeping.com/issues/2008-08/nftt/index.php

My total system volume is around 140 gallons. For the first 3 days I have been dosing .6ml. Today is day 4 and I will almost double the dose to 1ml. After 1 week I am supposed to add .5ml weekly however I really do not want to bottom out my nutrients so I might cut that down to .25 or less, depending on how testing goes.

Yes I know, im crazy.

Recent FTS
http://img.photobucket.com/albums/v325/Dr_digitaL/ftsoctober.jpg

[Amphiprion]

I don't think you are crazy for trying. I do think you may be taking a more difficult route, though. I'm on my iPhone, so bear with the assessment, but it doesn't look as though you have all that much plant mass... Increasing it may well do what you are looking for with a bit less trouble.

[djkms]

My plant mass is about the same as it was back when I was feeding 5 times a day though. Granted I had a ton of octhodes back then (my Moorish Idol has since eaten it all!). The only difference I can think of between then and now is the addition of 3 fish. I did also feed live phytoplankton back then but it would clear my system in 30 minutes, could phyto be that efficient at consuming nutrients? I also have a ton of macros in my fuge.

Here are some FTS done back when I was feeding 5 times a day:
https://lh4.googleusercontent.com/-V0HfS5o0xwc/TecGWSMTNSI/AAAAAAAADbw/JVcXTAwlJWo/s912/FTS20110501.jpg

https://lh3.googleusercontent.com/-2GTgHI-ivic/TecGW3tMkbI/AAAAAAAADb0/sqz6qXaiyGE/s912/FTS20110601.jpg

https://lh3.googleusercontent.com/-3LAdE4M467g/ThPBfj7FVhI/AAAAAAAADiU/GwmajuGE_Sk/s912/07012011.jpg

[lilalove]

Love this tank! It's very natural looking with the macroalgae mixed in with coral.

[Amphiprion]

I think you've just exceeded what the algal biomass can handle. I know in my seagrass system, I can't typically keep nutrients high enough and I feed a lot (and it's only 25g). Lighting shouldn't be an issue with the AI units, either. How often do you have to trim things back and how is growth overall? I wonder if the algae is being nipped enough to stall growth... Well, either way. If the current fish won't let you keep algae growing at maximal rates, a slight dose of vodka may be necessary. I still personally prefer algal assimilation, but whatever works best for you given your current configuration/stocking is what you should pursue. If it were me, though, I'd play around with the algae a bit more.

[djkms]

Growth has been good. I don't really have any nippers in my system except for my Moorish but he is well fed Nori and doesnt pick at the macros much. I trim back my fast growers once a month and my halimeda every couple weeks. I think I will just overload my fuge this winter and see how things go. I do want to at least maintenance dose vodka in hopes in getting my SPS to take off again.

I will update this thread with my progress.

[norskfisk]

Another tip, sorry not related to vodka:
Your algae have reduced their growth rate right? Could it be that they are lacking some micro nutrient? You could try dosing Seachem Flourish, which has pretty much every micro nutrient there is. I grow phytoplankton in a special refugium setup and it crashes withing a few days if I stop dosing Flourish, even when there are nitrate and phosphate present. I need to dose it every day since it seems like the skimmer or some other thing removes it. I tried dosing weekly, but it didn't work.