Small pond newbie asking for stocking advice

[Lynn G.]

Hello!  I have been building a glorified bird bath and/or oversized tub pond for the last year, and last week I made my first attempt at adding fish.  Half of them are definitely still alive and 30% are definitely dead, so I'm open to any suggestions.  The biggest issue seems to be the wild temperature swings we have had this weekenx - my pond seems to be shallow enough that the water temp has also swung wildly, from a high of 80dF the day I added the fish to a low of 63dF that same night, to a further low of 58dF last night (all water temps, not air).  I know that would be tough on any fish, but maybe there's a better choice of species?  I also expect, given the pattern so far, that water temps will get pretty warm this summer, maybe even over 90dF.

 

Here's the pond setup:

Southern New Hampshire USA

Full sun (currently 7:30am to 3pm)

Six interconnected preformed pond molds, total of maybe 150gal.  Lowest point has a solar pump up to the highest point, runs continuously in full sun and on a timer (10mins/hour) when overcast or overnight.

- Fountainhead into ~20-25gal (8 inches deep) pool

- spillway into 9gal shallow pool

- waterfall down to ~70gal Central pool with plant shelf, 15+ inches deep, partially buried

- spills directly into two successive shallow 2.5gal pools

- then spills into 2ft deep 20gal buried pool containing the pump back up to the top

 

Water conditions:

Well water - 8.1pH and minimal mineral content when tested at purchase (granite/metamorphic ground water)

Ammonia and nitrates both tested close to zero in the pond prior to adding fish

Flora and fauna:

Aquatic plants first added five weeks ago, additional plants added two weeks ago - some in aquatic media with fertilizer tabs, some free floating.

Aquatic plants include hornwort, American frogbit, hardy lily, Joseph's coat, pennywort, moneywort, spiral rush, chameleon plant, and a few others.

Some algae present, but not excessive

Dragonfly and mosquito larvae present

Wild leopard frogs have moved right in, all sizes.

 

Structure:

Each section of pond has some large 2-3 inch pebbles (box store variety bag, rinsed) at the bottom, plus some native trap rock (granite/metamorphic) and sections of oak limbs for underwater, surface, and bird perch structure.

 

Fish attempted:

- I added 8 tiger barbs to the uppermost section with the fountainhead (20gal).  Some of them made it into the adjacent 9gal pool.  As of yesterday morning, there are definitely 5 dead and 1 confirmed survivor, 2 unaccounted for.  I think the cold temps did the worst damage - I thought I would restock in a few weeks once the overnight lows stay above 60dF.  Seems like a good idea?  The fish shop I went to insisted the barbs would be a hardy choice, though they admitted they didn't have any pond experience.

- I added 2 blue dwarf gourami and 10 danios (5 leopard, 5... other kind) to the largest central pool.  The danios seem to like the current from the waterfall to the outlet.  It's hard to count those quick little buggers and there's lots of space to hide, but I have 1 confirmed dead danio, and I've definitely seen at least 1 gourami and 5-6 danios alive at the same time.

 

It's only been four days, so I haven't retested the water yet, but I'm pretty sure temperature has been the biggest issue.  There's plenty of food in there - algae, plants, mosquito larvae, plus some pellets I've offered a couple times.

I didn't add any fish to the 20gal section at the bottom with the pump, because that section has a lot of level variation - there are a couple of small leaks and trickles off the waterfall I need to fix, which accumulates into a few inches lost from that pool over the day.

 

Any thoughts or suggestions?  Thanks in advance.

   ~ Lynn

 

 

 

Edited June 11 by Lynn G.
Fixing upside down photos

[sumplkrum]

Yes, your overnight temperature is the biggest issue.
The pond doesn't look like it has a lot of water volume, so temp drops are going to affect them pretty easily.

The danios should be fine as long as the water stays over 60F. ... But tiger barbs and gouramis are not cold water fish and will suffer.

Other possible options would be white cloud minnows, rice fish, guppies. You could also do gold fish.

[mynameisnobody]

Tropical species won’t cut it with those temps. 

[JettsPapa]

Guppies will be okay with night time temperatures down as far as the mid 50's, so they'd be fine during summer, but you'd need to remove them and take them inside in the fall.

[Lynn G.]

On 6/11/2024 at 10:45 AM, sumplkrum said:

Other possible options would be white cloud minnows, rice fish, guppies. You could also do gold fish.

Would the white cloud minnows be okay later in the summer?  I expect to have the opposite problem before too long, with high temps.  July-August air temps here get into the 90s with high humidity.  The lows in the 50s overnight this week have really been a surprise, and I don't think we'll see much more.  It was all 70s and 80s the last few weeks, otherwise I wouldn't have even tried fish yet.

 

On 6/11/2024 at 10:52 AM, mynameisnobody said:

Tropical species won’t cut it with those temps. 

Yeah, I definitely wouldn't have added fish if I knew it would be in the 50s this week.  Trying to find a happy medium between weather now and the expected hot weather later in summer.

On 6/11/2024 at 11:36 AM, JettsPapa said:

Guppies will be okay with night time temperatures down as far as the mid 50's, so they'd be fine during summer, but you'd need to remove them and take them inside in the fall.

Thanks!  I definitely plan to bring them all inside in the fall.  How are guppies with higher temps?

 

Thank you all for your insights!

[sumplkrum]

On 6/11/2024 at 12:27 PM, Lynn G. said:

Would the white cloud minnows be okay later in the summer?  I expect to have the opposite problem before too long, with high temps.  July-August air temps here get into the 90s with high humidity.  The lows in the 50s overnight this week have really been a surprise, and I don't think we'll see much more.  It was all 70s and 80s the last few weeks, otherwise I wouldn't have even tried fish yet.

Should be fine. The good thing about ponds is you'll have shaded areas ... and with your running water setup, the flow will circulate the water so it's not just a stagnant pool sitting in the sun. 

Also, fish like humidity.  🙂

Your biggest worry is when to bring them inside in the fall.
I'm on the Connecticut shoreline and would do it in late September, but you're a bit farther North. After Labor Day you'll have to watch the overnight temps and bring them in before it starts hitting below 60F.

[JettsPapa]

On 6/11/2024 at 11:27 AM, Lynn G. said:

. . . Thanks!  I definitely plan to bring them all inside in the fall.  How are guppies with higher temps?

I'm in southeast Texas, where in summer it gets well up into the 90's almost every day, and often the low 100's, and it doesn't cool down much below the high 70's at night, and mine do fine outside (they are in shade all day).