RTC question

[The Veteran]

Hello all!

Im new to here and of course, Im looking for some help. Im building a pond just for a Red Tail Catfish. Its going to be about 4500 gallons and a max depth of about 4 1/2 to 5 feet. I live in Mesa, Arizona, and while our temps get hot in the summer it cools down in the winter to about 41 degrees F. Thats in the middle of the night on the coolest night with highs averaging about 66. Will my red tail cat be ok and adapt or will I have to provide some type of heating for him? Thank you for all your input!

[MatsP]

Obviously, 4500 gallon of water won't go from 75'F to under 60'F overnight when the air temperature drops to 40'F.

Your goal would be to keep a temperature of over 70'F at all times. Whether that can be achieved in Mesa, AZ without heating or not is not something I could tell you. A local swimming pool company probably could tell you what you can expect a swimming pool of a size of (say) 8 x 16 x 4.5 would do in such a night [of course, they may say "well, no sane person swims in their pool on the morning when it's about 50'F anyways, so we don't know"].

Now, the next problem is the opposite: Does it get too hot in the summer? Ensuring that there is some shade would be one possible solution [a big tree or some such], or a reflecting cover that keeps the heat out. Remember that these fish live in BIG rivers in nature, and will be pretty much the same temperature all year around.

If possible, I would recommend going a little bit deeper, perhaps 6-8 ft - it will keep the temperature more stable (as the surface will heat up/cool down, but at the bottom it will stay more constant), and give you a bit more water to keep chemistry stable, and give the fish a bit more depth for swimming in.

I've only ever spent a weekend in Phoenix - mid April, and that was definitely hot enough for me, with temps reaching into the 100'F region.

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Mats

[Richard B]

I'd agree with an increase in depth & would suggest 6 feet minimum. Shade in the height of summer is very important but i'd avoid siting close to a big tree if it loses its leaves in autumn, er i mean the fall!

A couple of large sheets of polystyrene 6x2 feet by an inch thick shouldn't be hard to come by & are a quick, cheap, easily removeable shade option (attach them together). You might also want to increase aeration in the height of summer too

[Chrysichthys]

I've only ever spent a weekend in Phoenix - mid April, and that was definitely hot enough for me, with temps reaching into the 100'F region.

The record high for Phoenix is 122'F. If the water ever got that warm, it would kill both the fish and all the filter bacteria.

I think it would be a good idea to go to a koi dealer and ask what people with koi ponds do about the Arizona heat.

[The Veteran]

Thank you for all your input, but I think you guys forgot the main point of the question was about the cold, not the heat. Also, the top 2 1/2 to 3 feet are the ones you want to pay attention to for they are the ones that have the greatest variation for temperature in the heat. I dont know about cold, thats why i was seeking advise, not for heat.

[Shane]

I could not tell for sure from your original post... is this an indoor or outdoor pond? If purely outdoor, the swings in temp (high and low) would be too much for a RTC long term (i.e. for more than a few weeks).
-Shane

[The Veteran]

Yea, its going to be an outdoor pond. I guess ill have to get a heater then. Thank you!

[MatsP]

I think what Shane is saying isn't ONLY that it gets too cold in the winter, but that the temperature gets too hot in the summer too, which is a harder problem to solve, as it involves a cooler of some sort. People who keep marine fish do this, but it's quite costly equipment-wise [particularly if you need to keep 5000 gallon, rather than 100g or so], as well as using a fair bit of electricity.

--
Mats

[Chrysichthys]

I think very hot weather, combined with a big redtail churning out nitrate and phosphate, could result in a severe algae problem. As a minimum, you would need permanent shade for the pond, in the form of a roof or canopy of some sort.

My question is, again, in Arizona what do people who keep cold-water fish in outdoor ponds do about the heat? I googled it and Arizona does have koi associations. Go and talk to a shop that sells koi; they'll have the local knowledge that we don't.