I have had an awful summer with my pond

[charlotteda]

I've had my water garden for 10 years but never a summer like this.

 My pond averages 15-20" deep and contains about 800 gallons of water - various water plants (lilies, some marginal) and just a few small goldfish that I rarely feed.

 I changed my filtration set up this year. I had been using a skimmer - Pond Mag 9.5 pump and the atlantic filto falls with a UV lilght too. I changed to

OASE AquaMax Eco Classic 1200 Pump
 and Oase Filto Clear 1600 filter with UV.
 (and had to put my skimmer back in)

 This system should be able to handle my pond size and fish load.

 Two things happened this year. One was not my fault and one was.

 It was REALLY hot ! It got hot early in the year and stayed hot - so the water temp was higher than normal.
 The dumb thing I did. With the new pond set up, I thinned my water lilies too much, hot water, lots of sun, little surface coverage.

 So I have this floating scum that rises during the day and goes away at night.
 I got into the pond and vacuumed 95% of the debris off the bottom. This thing is clean folks.
 I tried all types of Micro lift products recommended by my pond store.
 I did not feed my few fish at all.
 I added extra aeration for the hottest months.
 I did several major water changes (40%).
 All this to no avail.

 I ordered a pond test kit and checked water parameters. (When did they stop putting KH testers in the kits ? - I ordered it separately.) All test results were fine except ph was high. No amount of baking soda would lower it.

 We had almost no rain. No runoff goes into the pond.

 My pic was taken very early morning - scum just starting

 Now fall is here. Pond is cooling. Still floating yuck on warm days. My plants are slowing down but I find it curious that my water hyacinths seemed to die in the pond very early. This season is over but I need some pond expert advice for next year. I would hate to have to tear down the pond but I don't want to fight this again all summer. Should I drain it this winter ? Wouldn't that be worse for the fish.

 Any suggestions appreciated.

[Bob_A]

All test results were fine except ph was high. No amount of baking soda would lower it.


Won't baking soda raise your PH?

[charlotteda]

Yes, but I thought not past 8.5.   My water is soft.  I always have to add BS with a lot of rain or a water change.

[Bob_A]

Isn't 8.5 really high?

I'm sure that DPerry will chime in, he could probably help you out.

[dperry]

A new pond takes about three years to establish balance.  It takes that long for the microbes that create balance to reach high, stable levels. Mess with that balance and you start all over again. Firstly, your old filter system likely had well-established colonies of all the bacterial species that create balance.  When you put in a new filter system, those bacteria had to start up as in a new pond.  Secondly, doing large water changes (you said several at 40% each time) is throwing  the baby out with the bath water. In this case, the "baby" is the water chemistry.  Large water changes also set the balance back to near-new conditions.  Thirdly, soft water makes it difficult to change pH, no matter how much bicarb you add.  Sodium bicarbonate will, with hard water, adjust your pH to 8.4, but you need to add calcium to harden the water.  I'd advise using limestone to harden and buffer the water.  Fourthly, you mentioned "debris" that you removed.  If you don't have one, I'd surely add a bottom drain (one that sits on top of the liner). Stirring up the "mucky" kind of debris can cause all kinds of problems.  You have a skimmer and most skimmers have a provision for adding a line from a bottom drain. Yes, it was really hot here, as well, but my pond water, which is in full sun all day, stayed crystal clear, save for a few hours of "murkiness"after I cleaned my filters. In summer, that's every 3 to 4 weeks.  My pH levels stay between 7.6 and 8.2, varying throughout the day and from day to night  and have been that way for ten years. My pond is entirely concrete and I was told when I built it that the concrete would make the pH very high. It hasn't, but it also adds calcium ions to the water, making it a good buffer.  After all, cement is made from limestone.  I never add anything -- ever. I don't pay for what nature provides free. I don't subscribe to the BS put out by people interested only in taking your money for gadgets like ionizers, chemicals and the latest filter fads.  I do not do water changes -- ever, except that water that is changed when I drain my above ground lily pool for the winter and refill it in spring (less than 10% of the total water in the system), and that's once a year.  Nature's rainfall does the rest.  My approach is to set the pond up to work as an artificial ecosystem with as little intervention as possible and "don't change or fix what ain't broke".  In your case, I'd put in some carbonate rock (limestone), give it time to reestablish balance.  Constant fussing with it will just create more problems.  Now, I'll sit back and wait for the crowd to jump all over me and tell me how wrong I am and how they found this or that to "work like a charm" and how backward I am. After all, I'm just another old fart who hasn't kept up with the times.  I just apply what I learned from biology and it works well for me.  Others may have found otherwise, but I'm also amazed how much time and money a lot of them spend on the latest and greatest and how many of them are actually biologically illiterate.

[charlotteda]

Thank you for your insight.  As a beekeeper, I come across many different management philosophies.  It's not wrong if it works for you.  My little pos skimmer does not allow a bottom drain.  This was our first pond, it is built on a sloping terrain.  The walls field stone cemented no skimmer.  So, I'm stuck with small in pond skimmer.  However,  I find your limestone advice very intriguing and I will research that.  Thanks for your input. ????

[dperry]

Calcium carbonate is the cheapest, most available material to raise the GH and KH (general hardness and buffering capacities).  Raising those will make the water more pH stable.  Limestone is essentially calcium carbonate, but so are marble chips (marble is metamorphosed limestone), oyster shells and eggshell.  When you use eggs, rinse the shells (to remove proteins), crush them up and toss them in the pond.  They will help increase both calcium and carbonate ions.

[matherfish]

Thanks Don. I am glad we have members who can help with these kind of problems.