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I am just getting some good results in my fish-less cycle and pretty soon will be able to get some fish. This is my first setup so I want to go slow and easy.

I have a 1000 gallon tank and want to find out what kind of fish I should start with. I have read a lot on the forum on Trout and Blue gill. I am leaning towards Blue Gill. My tank stayed about 45-50 through the winter without heat and now it is about 53 to 54. I have seen it up too 58 but just added more water and it went down again. I can heat it to 60 or 65 but have not started that yet because I want to look into the correct fish for this area first. I would love to try Perch  or even Arctic Char but not sure if the char would be too hard to use.

What fish do you use in Colorado?

What is the high and low temp for the fish you use if it is one that I am thinking about?

Maybe there is something better for me to use please let me know. (Bass?)

What would be a good starting amount for this size tank? I can always add more.

Also I am going to be growing lettuce, basil and some tomatoes to sell mostly and then add in anything for myself.

PH is about 7.6 and the water is just starting to come through the ammonia cycle back to 0 in about 2 to 3 days so it should not be long before I am at 24 hours back to 0. My NO2 and 3 are just starting to rise so I am hoping I am getting close. Then after this all works get some fish.

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Joe, I'd do trout (rainbows or brookies).  They're easy to get a hold of and should do well in that range.

Hi Joe,

You ask some good questions. First, I'd be curious as to where in Colorado you'll be keeping the system, mostly to understand climate. I lived in Craig for 10 years, where we saw plenty of -40F every winter, I've lived in Denver, Grand Jtc, as well as Durango...all with very different climates over the 25 years or so I was there. I also raised fish in most of those areas. Running an outdoor system could be extremely challenging in some parts of the state.

I've found It's hard to compare the temp ranges between a tank and the wild. A 1000 gal tank is big and awesome. That said, my experience is that fish in captivity can not tolerate temp extremes like they can in the wild. I've seen this with bluegill and catfish, as well as perch and smallmouth. Obviously all of those species winter over in frozen Colorado lakes and rivers, but put them in a tank and for whatever reason (I can think of a few), they often won't survive big temp swings. Many go into a semi-dormant state in the wild, as do some of the fish I hear the Aussies talk about when their fish winter over in their tanks. That said, one major advantage you have is the ability to maintain higher DO levels year 'round than they would have in the wild.

I don't know anyone with an AP system, running trout in your area - don't even know if it's legal with the jacked up F&G laws.... I think it would be interesting to try some Kokanee fingerlings...Bluegill are great, but grow very slowly. There are some Perch varieties which I think would be great as well, but I wonder if they'd be like Crappie, in that they want live food, not pellets.

I'm afraid I haven't helped you years in CO were pre-AP - I was interested in small scale aquaculture at the time.

I'm sure some of the CO AP folks will jump in. Good luck!

@Chip I am in Kiowa south of Denver. The coldest I have seen in the 13 years here was -9 and not that often. My tank is below grade and temps during this winter were 45 to 48 all winter and right now it is 51. I have 600 feet of PEX on all sides and bottom of the tank and it is insulated to R21. The ground temp at that height stays about 45 all year so that helps a lot. So with the PEX I can heat the tank all year if I want with hot water from my wood water boiler. Not sure how warm the water will get too in the summer yet because I never had it running in the summer. The water is pumping out to rafts fully covered and their temp is 1 degree higher. The total system has about 2500 gallons so it will not be such a extreme change becasue there is so much volume. I do want to stay with a fish that I can use pellets eventually I will make my own pellets.

If I were to use Trout or Blue Gill about how many fingerlings should I start with?

Hi Joe,

I'm familiar with Kiowa. It sounds like you've done quite a bit of work. Rather than guess at the numbers (you are significantly larger at 2500 gals than anything I've run), I would defer to someone more experienced in larger systems as to stocking levels. The key is not to be confused by some of the "canned" formulas floating around as to stocking density. Until your system is fully cycled and matured, a very conservative approach is warranted. You've also got some water temp challenges - bacteria development and the cycling process may be quite difficult mid-40's to 50F. Any idea what temps might be once you are heating? Also, any way of regulating (thermostat) the temp with your system?

Bluegill are much more tolerant as far as water quality and DO (compared to trout), however, with the DWC (rafts), you will be keeping things quite clean and oxygenated no doubt.

If you are planning to cycle with fish (I am not a fan of fish less cycling for a few reasons), I believe 100 Bluegill to start would be fine. Some will say that's too low, but I prefer a low number and always seem to get my fish through the process (I most always use Koi when cycling). Go with big numbers and often folks will be fishing out the dead ones right off. Once you've cycled, it's much easier to increase numbers, as the established bacteria colony will easily adjust to the additional load. Responsible feeding, maintaining adequate DO, adding additional filtration (proper type and capacity) if required, etc. are all critical elements to manage.

As far as trout, I'm not comfortable making any recommendations as I don't have trout experience.

Post some pics if you get a chance - sounds like you've got quite a project going.

@chip  It seams that right now I am almost ready to put in fish.  I have been doing the fish less cycling and I have seen the ammonia pretty much go to 0 every 24 hours. I have been looking at Bluegill, trout and Perch from several suppliers in Colorado and just want to make sure they can eat pellet fish food. I was thinking about 100 fish to start. I have 2 systems exactly the same so I will get the other side going and then when the first side is doing good maybe add 100 more and get 100 for the other system.

As I was saying in the last post I have all the fish tanks and rafts with PEX under everything. I did not say that they were all connected to a hot water heater in the last post but they are. I have a boiler setup using all TACO zone valves and a variable speed pump that works great. I have a TACO zone controller that is connected to my own controller that reads the temps and if I want it to be 55 the zone valve will open for about 10 to 15 minutes and it will adjust and stay there for the day. I also have a 500 gallon water storage tank that is hooked up to a wood boiler(home made but works great) and that is a part of the water heater so it will be the main source and the water heater will be the backup. I will also use solar as money come in.

The temperature situation is working perfectly I can keep it warm in the winter. I just do not know what it will get too naturally yet in the summer because I have not gone through it yet. The water temp in the fish tank today is 54. I am seeing a rise of temperature so far. Yesterday I added some from the top up water that was colder so that is why it was 51 yesterday but it is back to 54 today. So what it will be when I hit mid July I will not know.

How warm can Bluegill tolerate?

I have 2 sweetwater air pumps and I have 10 12" air stones in each tank with a ton of air in the rafts so yes the water is clean with great DO.

Hi Joe, Bluegill live and thrive in some very warm waters throughout the country, I've run into them in Northern and Central California, Arizona, Mid-West and the South. Some of the waters they live in can get very cold as well. It's definitely a strong selling point for the fish. Just wish the darn things would grow faster (takes a good two seasons to get them to decent size).

My big concern from what you've shared is cycling at your current temps - low, mid 50's (which is better than the 40's!). I mentioned this to you previously and I've just recently seen new thread on the HQ site pertaining to bacteria development and cold temps. The data posted puts your current temps in the "slowed" growth rate or something along those lines. As temps go up things will certainly improve as to growth rates for bacteria. I did not research the source of the poster's data, though it did sound consistent with previous data I've read. Basically you're at risk if you put fish into the system and the bacteria can't keep up or the system becomes overloaded. Do some reading/research on bacteria and cold temps if you get a chance and see what you think. Like I said, there was just a thread started on the very subject on HQ and those guys are mostly very thorough with the facts and data presented.

Hi Chip, I received some info on Bluegill that cost $1.00 per 3-4" but she told me they eat fathead minnows. So I am not sure how to do that and if the $1.00 each is a good cost. If they grow slow then 3-4" is a good start.

I also received a cost from someone that can get me perch in 3 weeks at .25. That sound like a better cost. He said that they would need to be trained to eat pellets too. Again how do you do that?

If I get the perch I could start warming my waters up to 65 and that will help in getting the bacteria growing faster. I would have 3 weeks more for it to take place. He told me they can handle any cold temps here in Colorado as well as warmer temps too.  Had any experience with Perch?

Joe, you can train your fish to eat pellets. Start with a good supply of composting worms (or BSFL, crickets, mealworms, bay shrimp, whatever you can get that they like to eat), and chop them up into pellet sized pieces. Feed them a bit less than they want each time, so keep them hungry. It helps to have a schedule. They will attack the chopped worms when fed. After a couple of days, begin substituting pellets for worms, about 10% ever couple of days. They will eat the pellets on accident during the frenzy, and get a taste for them. In a couple if weeks, they will be trained.

I have bluegill, Sac perch, green sunfish, and crappie all taking pellets.

Awesome!! Now to find dried mealworms or BSFL. What does that stand for?

Black soldier fly larva. Google it, tons of info and free plans for constructing bins. They eat everthing that worms won't, and eat it fast. They self harvest when full grown, dropping right into fish tank. No mess, and no smell if your bin is taken care of.

Bluegill are easy fish and perhaps a good choice for a first season since you don't know how warm it will get over summer.  Track it so you know if trout would be a future option or not.

As to how many, well that depends on how much filtration you have and if you are removing solids or not.  Stock your fish tanks based on filtration (or stock less and add fish as you find they are needed.)  As noted you need more filtration to keep up with fish that actually eat at cooler temperatures (like trout) so you would stock less of those high protein eating fish.

As to the notes on the previous page about fish having more trouble surviving cold in tanks and things like that.  I believe that is mostly do to tanks often being of smaller volume and thus having faster temperature swings.  Like I know bluegill can survive being in frozen lakes in Michigan.  Well in those lakes the temperature chills down slowly and therefore the whole system, including the fish, have time to get used to the cooler temperature and get to a dormant state.  In a small tank I've seen temperature go from rather warm to cold overnight and came within a breath of killing half the fish in the tank.  Now all the fish were capable of surviving the cold but not a 30 degree F temperature drop overnight.  Now with a 1000 gallon fish tank and a raft system there will be much more buffer to temperature fluctuations so I doubt that will be a problem.

Okay I decided to get Perch because they are available in 2 weeks and the cost on Bluegills is 4 times more.

Thanks everyone in helping me on this.

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