HELP! Fishless cycling suddenly needs to be fish-in cycling

[Lynn G.]

Background:  I am entering the fishkeeping hobby completely backwards - I started with building a glorified tub-pond/water feature in my backyard (about 100 gallons total across 7 different pools, with a recirculating water current), then added plants, then added fish.  I knew I would need to bring the fish in for the winter, because the pools aren't deep enough for them to survive the cold, and I knew cycling tanks could take 4-6-8 weeks, so I started cycling two of my three tanks at the beginning of August.  Being ambitious, I went with the fishless "How I Cycle" method outlined at aquariumscience.org with multiple additives to provide nutrients to the various beneficial bacteria, with all the recommended initial additions (pond mud innoculate, triple phosphate fertilizer, baking soda, plaster of paris, baker's yeast, sugar, epsom salt, pure ammonia, iron sulfate, and my own hopeful creative source of nitrite, celery powder) - plus daily additions of ammonia, fish food, sometimes baking soda and celery powder.  Cranked up the aeration on the sponge filters and bubblers, cranked up the heat on the heaters, and let it all do its thing.  It seemed to be going well - the water cleared, ammonia is definitely getting processed from day to day, although I'm not very good about adding precise amounts.  I've been testing with test strips, and I started seeing bigger drops in ammonia day-to-day the last few days, so I did the full API test kit this morning - pH was sky high (my well water is 8.0-8.5 to start with), ammonia 1.0ppm, nitrite 0.5 or 1.0ppm, nitrate 5.0-10.0ppm (I just have a bad memory, I can't remember the precise shade now.)  Not bad for 15 days in, I added some ammonia and fish food and carried on.

So here's the urgent part:  around noon today, I checked the weather forecast and discovered the overnight low was supposed to be 49dF!!!  My ponds are relatively shallow and follow the air temperature fairly closely, within a few degrees - and the overnight lows all week are forecast in the mid-50s.  WAY too cold for the fish, and temps I wasn't expected for another month!  It's still summer!!  So I spent the afternoon (when I should have been sleeping, I work nights) draining the ponds and collecting the fish into 5gal buckets.  I figured my best bet was keeping them inside in the buckets overnight with sponge filters for aeration and heaters for warmth, lids to prevent jumpers, and hope the heaters aren't too much for the small volume and close proximity.  [Tiger barbs (7), danios (30ish), white cloud minnows (4), dwarf gouramis (2), and guppies (4) - tiger barbs separate from the latter two]

My thought was to do a 90-100% water change on the two 20gal tanks that have been cycling, and add the fish in, and just switch to fish-in cycling.  I have a third 29gal tank that I literally just got set up and started cycling two days ago, with all the same additions still fresh.  The original plan and the way the tanks are set up was:

Tank A - 29gal - heated to 76dF - dwarf gouramis and guppies + future otocinclus, low current, well-aerated, plant baskets at the top edge, moss ledges and some plants in substrate

Tank B - 20gal - heated to 74dF - tiger barbs and white cloud minnows + future bristlenose pleco, well-aerated, heavily planted in substrate

Tank C - 20gal - unheated + high current - danios + future flagfish + future hillstream loaches, some plants and moss

After all this explanation - my question is, should I only do a big water change on the two 20gal tanks that have been cycling for a few weeks, and put the fish in those (which will be temporary homes for some until the 29gal is ready)?  Or should I just change out the water in all three tanks, ignore all the additives, and divide the fish as originally planned?  I'm concerned about the additives being at levels that are toxic or harmful to the fish, since the tanks aren't fully cycled and the additives haven't been broken down by bacteria.  As long as I keep the tiger barbs separate from the gouramis and guppies, I have both options.

Does anyone see any concerns with either plan?

[Additional notes on fish distribution: originally there were 15 guppies and 8 danios in the ponds.  The danios bred and bred, while the guppies apparently died off or were easy for raccoons to catch.  I plan to add more guppies and maybe tiger blood badis to this large tank, and hopefully find homes for some of the danios.  Just in case someone thinks my fish distribution across tanks is odd.]

[Additional notes on pH: my well water runs about 8.0-8.5 pH, and clearly I didn't need to add baking soda to raise pH.  I was hoping for nitrobacteria to draw it down some, or I'd correct the sky-high number with a water change.  I know that I'll have to be careful with ammonia toxicity even at 8.0, but hey, no chlorine to treat!]

[mynameisnobody]

Why can’t you move whatever media is filtering your outside tubs? Move it to your tanks and you have an instant cycle. 

[Lynn G.]

Oh, they're not filtered like that.  It's seven interconnected preformed ponds with loads of plants, and... that's it.  There's a solar-powered pump that moves water up from the lowest pool to the highest pool, and it has a giant filter box, but that's really just to protect the pump.  Every plant and surface in the system is part of the biological "filter".

I did take pond mud from here to inoculate my new filters, and I will be moving plants over to the indoor tanks, I just thought I had a few more weeks for everything to establish solidly, and I'm nervous about harming the fish

[mynameisnobody]

Toss a ton of plants in, also rocks from out there and you should be good. I wouldn’t feed for a week, then start feeding lightly. You should be ok. Next year you may want to toss some sponge filters in the outdoor ponds. Have them sit in there so when the weather surprises you, you just pull a sponge out and move it indoors, easy peasy. 

[Tony s]

On 8/22/2024 at 2:48 AM, Lynn G. said:

my question is, should I only do a big water change on the two 20gal tanks that have been cycling for a few weeks, and put the fish in those (which will be temporary homes for some until the 29gal is ready)?  Or should I just change out the water in all three tanks, ignore all the additives, and divide the fish as originally planned?

That’s completely up to you, of course. The fish can be crowded into the 2 tanks for a small bit with no harm. But, I think I might just as well get all 3 tanks going. Just to save time and work later. I’d for sure do a big water change on the 29g to eliminate any potential problems. And possibly use some prime to detox whatever is left. Fish in cycle is not a lot harder than fish less as long as you keep an eye on the ammonia and nitrites. Nitrates are much less toxic, so a bit of a buildup is not going to be an issue.  Don’t worry about your ph, most of the country has the same. Most Fish easily adapt.

[Lynn G.]

On 8/22/2024 at 9:29 AM, mynameisnobody said:

Toss a ton of plants in, also rocks from out there and you should be good. I wouldn’t feed for a week, then start feeding lightly. You should be ok. Next year you may want to toss some sponge filters in the outdoor ponds. Have them sit in there so when the weather surprises you, you just pull a sponge out and move it indoors, easy peasy. 

 

On 8/22/2024 at 10:34 AM, Tony s said:

That’s completely up to you, of course. The fish can be crowded into the 2 tanks for a small bit with no harm. But, I think I might just as well get all 3 tanks going. Just to save time and work later. I’d for sure do a big water change on the 29g to eliminate any potential problems. And possibly use some prime to detox whatever is left. Fish in cycle is not a lot harder than fish less as long as you keep an eye on the ammonia and nitrites. Nitrates are much less toxic, so a bit of a buildup is not going to be an issue.  Don’t worry about your ph, most of the country has the same. Most Fish easily adapt.

 

Thank you both for your feedback!  I read your comments right away, but haven't had a chance to reply because I was so busy working on all this.  I was able to get the full water change done on both the 20gal tanks on Thursday and get the fish divided between those two on Thursday, plus getting some hornwort cleaned and into the tanks also.  Nitrites were between 2 and 5 after the water change (which is why I was so worried about the pH) presumably because of junk stirred up, but they were down to 0.25 and 0.5 Friday morning, and no fish issues.  Ammonia is at 0 - I think those tanks are in that spot where the ammonia is getting converted but the nitrite bacteria aren't quite built up yet.  Not feeding the fish just yet.  I plan on doing the water change on the third tank and moving some fish over there to alleviate crowding, but I probably won't be able to do that until Monday.  The upside of all this is that I finally got an actual count on the danio juveniles, and boy did I underestimate - 43 juveniles!  Plus 7 of the original adults.  43!!  So I have also been active finding homes for them as quickly as possible through Facebook fish groups - they should all be gone within the week, and that will *really* alleviate the overcrowding.  Then I'll need to start shifting the rooted plants in from outside, instead of just relying on the hornwort.  Oh, and the long term plan for next year is definitely to keep the indoor tanks up and running through the summer with some fish staying inside, and some fish taking a summer vacation in the ponds, so I will definitely be better-prepared in the future.

Thank you again, it was really helpful to hear from both of you so I could be more confident about what I was doing.

[Lynn G.]

High-current tank, currently housing the danio juveniles to be revoked, plus two dwarf gouramis and four guppies.  And three assassin snails.

 

Tiger barb tank, currently housing 7 tiger barbs, 4 gold white cloud minnows, and all the danios I am keeping (7 adults, 3 juveniles).  Plus a Chinese mystery snail that somehow made it into my pond (inside the uppermost barrel).

[reefhugger]

This has been in interesting topic.  I just wanted to say how much I love your outdoor pond.  It must be a delightful place to enjoy in the warm months.

[Lynn G.]

On 8/24/2024 at 4:44 AM, reefhugger said:

This has been in interesting topic.  I just wanted to say how much I love your outdoor pond.  It must be a delightful place to enjoy in the warm months.

Thank you!  It has been a fun project for the last two years, and I very much enjoy it.