Can I add baking soda and epsum salts while treating with PP

[Doug G]

Just started my PP treatment, 1000 gal pond with moderate fish load (about 12 koi under 16"). Been trying for weeks to get my GH and KH up over 100 by adding baking soda and epsom salts along with crushed oyster shells. Lost one small koi a week ago from, I think ulcer or ich, have seen a few koi flashing occasionally. Is it OK to continue adding baking soda and epsom salts while I do the PP treatment? I've been adding about 2 cups of each per day, KH and GH has been rising slowly.

[fly4koi]

Add baking soda, 1 cup per day per 1000 gal. IMO the stock level is a bit high, but if your filtration can deal with it then sure. GH is not critical, KH is critical.

[*Ci*]

Epsom salts are magnesium, and by itself does not give a balanced gH. You should be adding equal parts of calcium (such as in calcium chloride which can be purchased in bulk at pool supplies and hardware stores). Do not rely on oyster shell, it does not dissolve evenly or predictably.

While not as critical as kH, Dr. Roddy Conrad felt that these minerals were important for proper koi growth, and certainly for plants, if you have them. My tap water here on Vancouver Is. has zero gH and kH, so I add both mineral salts to bring my gH up to about 5-6 dgH, and baking soda to 7 dkH for stability with each water change. My pond is roofed, so no need to adjust for rainfall bringing th kH down, otherwise you need to monitor the levels after heavy rainfalls, and adjust accordingly.

If you add the proper amount of these components, there should be no need to wait for weeks to get the numbers up - if your test kits are not showing changes, then test them out on a small sample that you know has a given kH/gH and see if they are still viable. How frequent and how much of water changes are you doing?

Potassium permanganate does not react with baking soda, epsom or calcium chloride, but I would feel more comfortable doing them on different days. Calcium chloride and baking soda should not be added together, but within an hour or so is fine.
How close are you to your target numbers for gH and kH? I would go ahead and get that adjusted within the next couple of days, and then do another pp treatment.

https://www.homehardware.ca/en/20kg-...ride/p/5548231

[*Ci*]

I, too, would consider 12 koi in 1000g to be heavily stocked, even at less than 16” each. If they are presenting with ulcers, ich and flashing, I would certainly look at water quality. Test for ammonia, nitrite and nitrate, do a thorough cleanout and some large water changes. What is your filtration? Does the pond have rocks or bottom drains? Is there a buildup of mulm on the bottom or in the filters?

[Doug G]

Thanks for the replies, before I respond perhaps I should give a little more description of the pond.

The pond is in our backyard right next to the Fraser River in New Westminster BC (part of Metro Vancouver). The pond is about 25 years old and is all DIY. The pond water volume is estimated at 1000 gal, Approximate dimensions are 7ft x 12 ft. with a maximum depth of 2 1/2 ft. Water level is maintained by a water level control valve (like in a toilet tank) which is fed from a carbon filter to remove chlorine. Air is added thru an airpump with 2 airstones in the pond.

Water filtration is a four stage process. Water is pumped via a submerged pump thru a swirl filter, from the swirl filter the water is gravity fed thru a UV filter to the bottom of an up-flow main bio filter which discharges to the waterfall which flows into the bog and then returns to the pond. A bypass line allows bypassing the UV filter and main bio filter directly to the bog.

The swirl filter is used to remove solids from the water and also introduces more air into the water to increase oxygen levels. Water enters the swirl filter canister (a round 20 gallon plastic garbage can) about 6” from the top thru a pipe elbow which directs the water around the perimeter of the canister. The suspended solids in the incoming water drop out of suspension as the water velocity slows down after exiting the 1 ¼” pipe. A bottom drain is used to periodically remove the collected solids. Water exits the swirl filter thru a 1 ¼” elbow facing upward in the quiet zone in the middle of the garbage can about 2” below the top. As the water enters the elbow air is also drawn into the elbow (you can often hear a gurgling sound) thus adding oxygen.

The water flows by gravity from this point thru the UV filter to the main filter. The main filter in a 50 gal Rubbermaid garbage can is an up-flow design containing both mechanical and bio filter medium. Water enters thru a 1 ¼” fitting about 6” from the bottom giving suspended solids another place to drop out as the water velocity slows down and then flows upward thru 2 layers of filter medium (coarse and medium) and then thru a third layer of bio filter medium. The bio filter medium is made up of polypropylene rope which has been cut to about 12” length and unwound into individual fibres and some scraps of leftover filter medium cut into 2" chunks. This provides substantial surface area for beneficial bacteria to grow. Water then flows out of the top of the main filter over the waterfall where additional air is entrained and into the bog. Plants in a basket on the top of the main filter act as an extension to the bog.
The main bog is filled with river rock and pea gravel as a growing medium for bog plants (marsh marigold, irises etc.) The piping for the filter system also includes valves and bypass hoses, drains, a vent and overflows directed into the bog.

The system seems to work well, we have clear water, rarely have any measurable ammonia and over the past 5+ years or so have only lost 2 or 3 fish. Our current fish load is significantly reduced from the last few years as we sold off 15 of our largest koi, most over 24" this spring and 4 of our largest fish 2 years ago. Many of our koi were born in the pond, we bought 2 new 4" to 6" koi this year and our last purchase of fish before that was 4 or 5 years ago.

Just read thru Dr Roddy's thread on PP last night, have to admit much of it was over my head but I did learn a few things. Have used PP in the past, for a while it was part of our regular spring startup routine, we learned it from Roger Pinnete of Ponds Beautiful in Langley BC over a decade ago. I think anyone in the lower mainland of BC probably knew Roger, not as impressive as Dr Roddy but a wealth of knowledge. Don't know if he was ever a member here.
Our tap water is also low in KH and Gh, mainly rain and snow melt collected in the mountains. I'll wait until tomorrow to add the BS and ES and pickup some calcium chloride. My test results may be questionable as I was using some old expired test kits but I started using new kits this week. My KH today is 90 up from 70 yesterday (target 120 to 240 ppm) and GH is 100 up from 60 (target 120 to 300 ppm). Don't usually do regular water changes (what criteria do you use to determine when to do it?), often have enough leaks from the waterfall to not need additional changes.

Sorry to be so wordy, just thought it would be useful to you to know more about my pond. I welcome any questions or advice.

[richtoybox]

If you are having problems getting the KH up, try turning off the water level control valve for a couple of days to see how much water is being added to the pond. If your tap water values are zero, and there is a leak causing large additions of tap water to the pond, then that may be part of the problem. If there is not a leak, with the current level of KH, you should be able to add massive amounts of baking soda to achieve the higher levels. I would suggest that before adding the baking soda, you get as accurate a KH value as you can, (I used to take 4 or 5 test tubes of water into a clear glass, and then add the drops of test solution, (knowing each drop was then worth 1/4 or 1/5 of a degree - about 4.25 or 3.4 ppm) and then using the calculator (https://www.koiphen.com/forums/koicalcs.php?do=calckh) add a reasonable amount of baking soda of known weight, ie 1 pound, 2 pound or whatever size container full, and then remeasure the KH. From the shift in the KH, you can calculate the total pond volume. Most ponds unless truly verticle sides, and flat bottom are estimated with length width depth, and are estimated at a much larger volume than they actually have, making treatments potentially dangerous, and much more expensive than needed.

[Doug G]

If you are having problems getting the KH up, try turning off the water level control valve for a couple of days to see how much water is being added to the pond. If your tap water values are zero, and there is a leak causing large additions of tap water to the pond, then that may be part of the problem. If there is not a leak, with the current level of KH, you should be able to add massive amounts of baking soda to achieve the higher levels. I would suggest that before adding the baking soda, you get as accurate a KH value as you can, (I used to take 4 or 5 test tubes of water into a clear glass, and then add the drops of test solution, (knowing each drop was then worth 1/4 or 1/5 of a degree - about 4.25 or 3.4 ppm) and then using the calculator (https://www.koiphen.com/forums/koicalcs.php?do=calckh) add a reasonable amount of baking soda of known weight, ie 1 pound, 2 pound or whatever size container full, and then remeasure the KH. From the shift in the KH, you can calculate the total pond volume. Most ponds unless truly verticle sides, and flat bottom are estimated with length width depth, and are estimated at a much larger volume than they actually have, making treatments potentially dangerous, and much more expensive than needed.

Good suggestions, just checked my level control and it was flowing (Dam, I thought I had eliminated all leaks, might just be evaporation I hope.) Kh is starting to move, up 20 ppm from yesterday after adding 2 cups of BS. I'll shut off the level control overnight and see what the level does. Like your idea of testing a larger volume to get more accurate results and calculating volume from KH shift, been wondering if there was a way to do that for a while. How long after adding BS should I wait to ensure the KH shift is complete? Does it depend on pumping capacity vs estimated pond volume? Not sure of my pump size, might have to pull it up and check the model number. Tomorrow is a busy day but maybe I can try in on Sunday.

Just to clarify, in order to calculate volume from KH shift with given weight of BS added, I need to add BS only and not along with epsom salts?

[*Ci*]

Your questions might be answered in this thread;

https://www.koiphen.com/forums/showt...ng-soda-method

The epsom salts will not effect kH and pond volume measurement.

[Doug G]

Thanks Ci, I think I understand the method described in the linked thread so I'll try it overnight tonight with the refill valve closed and at the same time estimate my leak. When I shut off my refill valve I confirmed I do have a leak and today I could see some signs of the leak near the waterfall. It appears my refill valve is able to maintain pond level despite the leak so in essence I have a constant water exchange, just not sure how much is exchanged daily.

[Doug G]

Looks like Richard hit the nail on the head, no need to shut off the refill valve for days, I saw a substantial drop in hours. Been chasing the leak for the last few days, thought I had it isolated to the waterfall but today found part of the bog was overflowing. Still not having much luck getting KH, GH and PH up where I want it due to the leak. KH and GH are under 100 ppm and PH is 7.1.

[Doug G]

Got the leaks stopped, what threw me off was I thought the leak was stopped so I turned the refill valve back on and didn't realize it was running continuously. The ground around the pond is so porous (almost pure sand) that there was no visible sign of the leak. With the leak stopped, the calculated volume using the KH calculator, is about 2100 gal which agrees with my recollection from when I built the pond. I misplaced my original binder with all my notes and when I did a quick calculation messed it up when I said it was 1000 gal. After a week of adding BS and Epsom salt my water numbers are more in line with my targets:

KH 140 (target 120 to 240) ppm
GH 160 (target 120 to 300) ppm
PH 7.2 (target 7.5 to 8.5) not sure why it is still low so I'll keep monitoring and adding BS
Nitrite 0 (target 0 to 0.1) ppm
Nitrate 5 to 10* (target 0 to 50) ppm * range because I find it hard to exactly match the sample color to the chart
Ammonia 0.3 to 0.6* (target 0 to 0.1) but according to the test kit instructions below 1.2 ppm is acceptable. I think the ammonia is due to shutting down the bio filter to repair the leak and the PP treatments (3 treatments 4 days apart). I think for future PP treatments I'll bypass the biofilter. Due to my previous uncertainty with pond volume I did the PP treatments with 2 teaspoons initially followed by 2 additional teaspoons 2 or 3 hours later.

Also started adding calcium chloride and Koi clay, water is crystal clear, fish are acting normal.

[richtoybox]

Leaks are always a problem. Glad you got them corrected.

[Doug G]

Any comments on splitting the PP treatments into two half doses 2 hours apart? Good idea or bad? Also is it a good idea to bypass the bio filter during treatment? I can bypass my bio filter but then it has no flow so won't that harm the bacteria also? Based on some recent reading, I'm going to add an airstone to my bio filter and move one of my two airstones in the pond to the top of my submersible pump. I realize real koi ponds have bottom drains not submersible pumps but no way to go that route now so I'm trying to make the best of what I have.

[richtoybox]

PP is an oxidizer, and for parasite eradication, it is important to have a strong enough dose, long enough. Many would do multiple doses, 2ppm on day one, 2ppm on day 2, 2ppm on day 3, etc. until the 2ppm would maintain the pink/purple color for 10 to 12 hours. This may be possible if the filters are taken off line, but due to the large amount of detritus and bio material in the filter, I was never able to keep the color for more than a couple of hours. I went to the use of permanganate test strips, so that I could tell when the concentration dropped, and then add about 1ppm to boost it back to between 2 and 3ppm. I always considered that the entire system needed to be treated, not just the pond, but Doc Johnson in his book Koi Health and Disease has a 5 day treatment with filters off line, using 2 to 4ppm each morning. This does not require watching for a color change.