Reading pH levels...

[audioenvy]

I'm new to this pond hobby. I recently purchased a home that has a garden pond and I've been trying to learn things and make adjustments so that it would support fish:

Pond size: About 700 gallons, filled about two months ago
Pump/Filter: Savio pump/skimmer with filter, a waterfall, and an additional pond filter (Beckett BF700)
UV Light: None yet but it's on my list
Water changes: I don't yet have a high power pond vacuum. I tried a shop vac but it's useless.
Treatment: I use a sludge remover liquid and an algae control powder about once a week
Silt Level: there is a 1/4 inch layer of silt on the bottom that I would try to remove if I had a vacuum

Fish count: 10 small pet store koi purchased as an initial test (I'll give some away as they grow)
Fish health: they seem to be doing great, definitely getting bigger. More active at certain times of day than others.
Feeding: Once a day, sometimes skip. Fish seem to be eating stuff on the rocks and sides.
Fish demeanor: fairly skittish but there's a garter snake that lives in the rocks that pesters them
Plants: basically none
Sun: full sun much of the day

I have the API Pond Master test kit and tested in the mid-morning. Here are my findings as best as I can tell:

- pH level is greater than 8 but definitely less than 9. Probably low-to-mid 8s if I were to extrapolate?
- Ammonia level is definitely less than 0.25. I'd guess 0.10 if I were to attempt to extrapolate.
- Nitrate level is essentially zero
- Phosphate levels are essentially zero

Here is a comparison of the pH of the water from the pond compared to what comes out of the hose (which is what I used to fill the pond after treating the water with a de-chlorinator powder):

There's an ever-so-slight difference between the pond (on the left) and the garden hose (on the right).

- Am I crazy or is that a pretty high pH level coming out of the hose?
- Should I try to use different water to refill the pond (that would be a challenge LOL)
- Is there a permanent pH lowering treatment?

Thoughts?

 

[Meyer Jordan]

As long as the pH remains under 9 and is relatively stable I would not be concerned.
Some municipalities artificially raise the pH of the water supply to restrict mineral buildup in the plumbing.

I am curious as to why 2 month old pond would have any appreciable amount of sediment.

 

[addy1]

I am curious as to why 2 month old pond would have any appreciable amount of sediment.

I think he moved into a house with a pond already in place, and changed the water two months ago. That is what I am reading.

 

[Meyer Jordan]

I think he moved into a house with a pond already in place, and changed the water two months ago. That is what I am reading.

Could be, need a clarification.

 

[audioenvy]

I think he moved into a house with a pond already in place, and changed the water two months ago. That is what I am reading.

Yes. I bucket drained as much water as I could remove and refilled it but did not completely replace all the rocks and/or scrub the liner. There was still some existing sediment. I'm not sure if it's increasing or just the same amount that was there already.

 

[Meyer Jordan]

Thanks for the clarification. I would not worry about a little sediment.

 

[morewater]

Get some marginal plants in there, as well as some lilies (look up on this forum for how to "koi-proof" your lilies). If you have marginal and some lily-pad cover, you'll cut down on your algae growth, thus negating the need to add algae control products.

Sounds to me like you don't have much in the way of "sludge", so why bother. A decent filter will take care of most of your suspended sediment (which settles to become sludge).

Never, ever "scrub" your liner.

Hold off on a UV until after you've put in the best filters that exist.......plants.

Everyone seems to flock to the UV like it's the Holy Grail of Pondkeeping, when oftentimes it's wholly unnecessary and merely masks and band-aids an underlying problem.

Keep your water changes to an absolute minimum, if all all.

JMHO, but I'm stickin' to it.

 

[Meyer Jordan]

Double Ditto!!

 

[audioenvy]

Get some marginal plants in there, as well as some lilies (look up on this forum for how to "koi-proof" your lilies). If you have marginal and some lily-pad cover, you'll cut down on your algae growth, thus negating the need to add algae control products.

Is there a place to buy pool plants online?

 

[morewater]

Google water garden centres in your area.

Go have a look at what they've got, then make your choices.

 

[bettasngoldfish]

With 10 koi in 700 gallons of water you will need to do water changes to keep decent water quality. If not as they grow you may find you start to have trouble with water quality and fish will start to get sick.

 

[audioenvy]

Ok, so last week both the tap water from the hose and the pond water were similar and were both above 8.0 pH. I measured both again today (tried to do it at the same time of day) but the tap water was at 6.0 and the pond water was 7.0. I'm not too worried about the pond because the fish seem fine and the nitrate/ammonia levels are still the same as a week ago but I'm wondering what would cause such a crazy drop especially in tap water? I don't have a KH tester unfortunately but sounds like I might need one.

I'll measure the pH again later in the day and see what it's at. I'm assuming if I need to add de-chlorinated tap water to the pond (should I need to do water changes at some point) I need to be cautious of the pH and add baking soda?

Fall is approaching and the weather has turned cool. Probably 20 degrees lower outside than it was a week ago. But that wouldn't change the pH would it?

 

[Meyer Jordan]

Ok, so last week both the tap water from the hose and the pond water were similar and were both above 8.0 pH. I measured both again today (tried to do it at the same time of day) but the tap water was at 6.0 and the pond water was 7.0. I'm not too worried about the pond because the fish seem fine and the nitrate/ammonia levels are still the same as a week ago but I'm wondering what would cause such a crazy drop especially in tap water? I don't have a KH tester unfortunately but sounds like I might need one.

I'll measure the pH again later in the day and see what it's at. I'm assuming if I need to add de-chlorinated tap water to the pond (should I need to do water changes at some point) I need to be cautious of the pH and add baking soda?

Fall is approaching and the weather has turned cool. Probably 20 degrees lower outside than it was a week ago. But that wouldn't change the pH would it?

Temperature has no effect on pH.
I find it very strange that your source water would vary that much in pH. Is this well water or from a municipal supplier? If municipal, I would call them and ask if they have made any recent changes in water treatment. Ask them about the pH.
Before I added any more water to your pond I would ascertain whether the problem is indeed with the supplier or your pH test kit is giving erroneous results.
It is a good idea to have a KH test kit on hand.

 

[budgenator]

It could be that the silt is just dead/dormant algae, rather than spending money on a pond vac, try having a pump on the bottom of the pond and send the "silt" into the filter to be removed. At two months the filters are probably just starting to work biologically, given your in Utah, things are unlikely to settle down until the water gets up to about 55 degrees next spring.
It's normal for a pond in the spring as the water warms up to turn green (sometimes to peasoup), then clear, be patient. Clean your filters but not too clean, the bacteria growing in them protect your fish by cleaning the water. Weekly 10% water changes help remove build ups of nitrates, and are very helpful.
Sludge removers are probably a waste of money, algeacides often do more harm than good, at best they are a quick fix for what would have happened anyway, at worse they cover up the underlying problem until the fish get hurt