Aloha Cathy,

I have made water gardens out of stock tanks in the past and plan on doing so again. The first thing that I would want to know is if there are any small children or pets that might fall into the tank. We wouldn't want anybody to tip in. I would use some nice lava rocks to make a stairway up on side of the tank so that any animal that found themselves in the tub could climb out. This would also create a safe place for birds to come and get a drink. I'm not sure what type of ornamental water plants are allowed in Hawaii. If there is no danger of introducing an invasive plant I would consider lotus and tropical water lilies. I have white lotus that are marvelous but they need to be confined in a water tank like yours so that they don't get out into the wild. The leaves, flowers and seed pods are all beautiful. There are day and night blooming tropical lilies that are beautiful and fragrant. If you have any native fish that have viable populations in the wild I would see if you could have them control your mosquitoes. I have noticed a type of biological control of mosquitoes that is a type of Baccillus thurengensis (might have the spelling wrong). This is a bacteria that infects mosquitoes. Water gardens are beautiful and can serve as a source of water for wildlife. Good luck.

David

Aloha David,

Thanks for the lava rock "ladder" idea, we do have critters that will probably end up in there at some point. The chickens by accident and the border collies by choice, probably. I guess we will need "dog proof" water lilies.

A fragrant lilly would be nice, perhaps some water grasses as well. I don't think the plantings will stay put, though, since there will be swimming dogs pushing them about so I was thinking a lot of the plants would be planted alongside the stock tank instead of directly in it.

We don't have much "wild" fresh water, just the occasional stream that goes to the ocean so there aren't a lot of local freshwater fish. We do have lots of salt and some brackish water fishes. I was thinking guppies and koi to eat the mosquitoes. Hmm, maybe some prawns would work in the pond. I don't know if they eat mosquitoes, though.

Does a water garden pond have to be drained every once in awhile? I'm thinking of either putting it up in the back of the yard by the shed where the bees can drink from it. I'm putting a lanai (porch) on the shed since it has a lovely ocean view. A nice water garden at the edge of the porch might be nice. The other option for the tank would be down the hill by the house. Just outside what will eventually be the dining room window. I could set it in the hillside and perhaps put a fountain from the hillside behind it into the tank. A wall "mask" fountain. The drain would be easier from the upper location, but we could use the tank fountain as the "diversion" load from our wind generator. (Sometimes we need to waste power when the wind blows too hard.)

I believe that you wouldn't need to empty the water tub if you have aquatic plants taking up the nutrients that the fish produce. With the right balance of plant and animal life you could establish a sustainable water garden. The sound of running water is wonderful and also oxygenates the water making it a better environment so a fountain would be a great addition. Fish....I would choose guppies over koi to control the mosquitoes since koi are plant eaters and also need a larger amount of water to do well. How about using wire that they use to reinforce concrete to cover the tank so dogs and chickens couldn't get in. Lotus leaves and flowers would be able to come up through the wire. I would also bury the tank so that it's sides don't stand out. Have fun with your project.

David

Aloha Cathy

David has given you some excellent suggestions. if you want more information try the Ponds and Aquatic plants forum on this Garden Web.

I recently put in a new pond in Kailua Kona.

There is also West Hawaii Garden Club on: www.westhawaiigardenclub.gov that has a lot of instruction and ideas about ponds.

If you have a pond, you will have toads, Cane Toads, introduced to Hawaii to kill bugs in the Sugar Cane. Everything about them is poisonus. The poison can kill a small dog or cat. Nothing to be afraid of but to be aware off.

Good luck with your Pond.
Phil

Aloha Cathy, why not come to one of the Big Island Water Garden Club's meetings? We meet on the third Tuesday of every month at the Komohana Ag. Complex in Hilo. And, to answer your question, a stock tank makes a wonderful pond. The guppies will eat the mosquito larvae, but koi are usually to big to do so. Everyone is welcome.

I didn't mean to belittle the West side's club, they are wonderful people and we of the east side are having a field trip next month to attend their meeting. And David Vermont gives excellent advise; and yes, we do have a big variety of lotus here, probably the largest variety in the U.S. There are also lots of different waterlillys available although at your elevation, "hardy" lillys seldom bloom. Lots of tropicals though. Maybe KonaPhil is a member of the west side club, and I'll get to meet him next month.

For those who might wonder about our conditions here, altitude means a lot. I am at 750' and my temperatures are almost 10 F lower than at the beach below me.

HI, we brought over our prefab pond from Maui and have put small fish in it to try it out..like we have swordtails, neon tetra and somewhere in it are some platties..We started out with 6 swordtails,4 neon tetra and 4 platties..they have multiplied in the 3-4 months they've been in the pond. We have water plants..can't remember the full name its a water h....with a lavender flower and a lettuce or cabbage plant..BTW, I joined your Hilo pond group but have never gone to any meetings as I believe they are held at 7pm and I don't drive at night. :(. I also saw your display at the orchid show a few months ago.(very nice!!) I am getting a deflatable pond I bid on ebay and won ..it holds 45 gallons of water..gonna put the small fish in it and get some goldfish for the bigger pond in our rock garden.
Shirl