Some questions I have

[richyd]

Hi Completely new to this and have numerous questions.
Firstly My parents had a 4000litre pond with koi, goldfish, comets etc. Some were 12 years old.
Late summer last year the fish started dying one by one. Broke my mums heart. I knew nothing about ponds but tried my best to find out what was causing this. They had a simple hozelock pump going into a gravity bio filter. I had the water checked out by my local aquatic centre and they said it was fine. Still to this day I have no idea what caused the fish to die. When I pulled them out I inspected them and they showed no sign of disease.

After this I decided to cheer up my mum again. I striped out the pond liner, extended the pond and installed a new rubber liner and rebuilt a waterfall. The pond now is roughly 5600liters with a 8000lt/h pump and a 10000 litre Oase pressure filter. Filed it all up, added dechlorinater and added a few lillies, and some assorted marginal plants. Left it running for a month then added a few goldfish. They all seemed fine after a week so decided to add a few koi, shubunkins, comets. They are all getting on fine and feeding well.

However, I'm still having various issues, and things that I really don't understand.

The waterfall was cemented together, however, I let it cure properly before using. When I first tested the water it was reading 6.5 in the morning and 7.7 in the evening. Now the readings have risen. Seems to have stabilised at 8.1. Is this acceptable and safe for the fish.

Also, my pressure filter indicates when it needs cleaning. you just turn a switch and pull a handle which cleans the sponges and the dirty water exists to a flower bed. When performing this maintenance what happens to the beneficial bacteria? It doesn't wash away does it?

Sorry to ramble on somewhat, I just want to see my mother happy again.
Thanks in advance

 

[JenH]

Sorry your mom lost all her fish. Heartbreaking. Cement/concrete tends to raise the pH of the water a bit, I believe because of leaking lime into the water. But from what I have read it also creates a pretty good buffer from pH fluctuations as well. 8.1 is ok for your fish, it's usually more harmful for them to have the pH constantly changing then for it to be a little high but constant. My pond is always right around 8.3 and all the fish are doing just fine. I don't know anything at all about the type of filter your using, etc. But simply flushing your filter should not harm your established bacteria. If you were running chlorinated tapwater to clean the filter, that could harm your bacteria. But also, once your pound has cycled you would have the beneficial bacteria on every surface in the entire pond, so even if a few of them come out when you flush they will multiply and fill that area up again quickly.

Just remember it will take several weeks after adding fish for everything to cycle, you rally don't have the bacteria until you add the fish and the begin to produce ammonia. The fish release ammonia which start the bacteria colonies, that turn it to nitrites. Once the nitrites start to build up then come the next bacteria who convert those nitrites to nitrates for your plants to use. But before the bacteria begin to multiply and colonize there has to be high enough levels of ammonia and nitrites in the pond. That's why it normally take 6 weeks or so for a new pond to cycle. Hope that helps.

 

[richyd]

Thanks for the swift response Jen. Much appreciated.

One question I forgot to ask is regarding water changes. My parents did not do this in the past, but I read somewhere that water changes are necessary. Just don't know at what intervals / volume of water to removed.

Also when filling the pond back up with tap water (whilst the fish are still in the pond) do I add the treatment before or after filling. Or do I have to premix.

 

[sissy]

add the treatment before and really I don't do water changes anymore and find no need for them .I just top the pond off and your ph is fine as long as you can keep it stable .I really not sure how many fish you have but over feeding can cause more problems as they will produce more waste .What did they say when they tested you water (fine ) not sure but my pet store gives me a read out .

 

[Sheetmetalman]

I'm like Sissy--I dont do water changes either--never have. My pond is around 5000 gallons and between evaporation from heat and running my waterfall and the fact that I use about 5 to 15 gallons out every couple days to water my new trees and a lot of my plants I refill it once a week and thats good enuff--I have never lost a fish ( well I did loose one albino catfish last winter that was hid in the leaves that I removed from the pond bottom). I have 40 small gold fish and 35 Koi and goldfish between 4 and 9 inches long.