Aquaponic Gardening

A Community and Forum For Aquaponic Gardeners

I just lost 3 tilapia yesterday, and one a couple days before that, out of about 25 in this tank. For the life of my I can't figure out why they died.  They were all about 3 - 4" long and I've had them since mid-December.  pH = 7, Ammonia, Nitrite and Nitrate levels all close to zero, temp - 72 F.  and plenty of oxygen.  A clue to the mystery, though, is that I've lost fish inexplicably in this tank before, and it is the only system we used PVC glue in. Could that be it?  I've included a couple photos from my iPhone...hopefully they aren't as crazy big as they look now!

Views: 815

Reply to This

Replies to This Discussion

I have used pine needles, barley straw, and vinegar (cheap, but be very very careful), and all of them work. but now, with water dripping through the small pockets of peat in my towers, my pH stays naturally very low, even with slightly basic water- I lime on a regular basis.

Jeff Givan said:
Hey folks, anyone got any great and inexpensive ideas on lowering the ph in my pond. As I have said in the past our tap water is very high in PH. I just tested my pond again and it is still in the 9.0 area. In the past I have bought some PH lowering acid, but it is very expensive and with about 4000 gallons it won't be cheap to keep it in range. I have tried adding some spagnum peat moss to help lower it over time, but it just isn't working. I am getting nutrient lockout for sure. A lot of my leaves are pale yellow and surely aren't getting enough iron. I need a reasonably priced fix if anyone has it!
Thanks
Doesn't the lime make the PH higher? What kind of peat moss do you use in your towers? And, how much? For 4000 gallons what would you suggest if I use vinegar. I also need to figure something out to keep it that way, because when I add water it will be high again. I suppose that I could treat the water before I add it too the pond, the only problem is that I lose a lot during this time of the year due to evaporation and some leakage so I would need to premix it in a large vessel before adding.

Nate Storey said:
I have used pine needles, barley straw, and vinegar (cheap, but be very very careful), and all of them work. but now, with water dripping through the small pockets of peat in my towers, my pH stays naturally very low, even with slightly basic water- I lime on a regular basis.

Jeff Givan said:
Hey folks, anyone got any great and inexpensive ideas on lowering the ph in my pond. As I have said in the past our tap water is very high in PH. I just tested my pond again and it is still in the 9.0 area. In the past I have bought some PH lowering acid, but it is very expensive and with about 4000 gallons it won't be cheap to keep it in range. I have tried adding some spagnum peat moss to help lower it over time, but it just isn't working. I am getting nutrient lockout for sure. A lot of my leaves are pale yellow and surely aren't getting enough iron. I need a reasonably priced fix if anyone has it!
Thanks
I have used vinegar in hydro systems very cheap. But be careful make any adjustment slowly any dramatic swings can be deadly to both fish and plants

Jeff Givan said:
Hey folks, anyone got any great and inexpensive ideas on lowering the ph in my pond. As I have said in the past our tap water is very high in PH. I just tested my pond again and it is still in the 9.0 area. In the past I have bought some PH lowering acid, but it is very expensive and with about 4000 gallons it won't be cheap to keep it in range. I have tried adding some spagnum peat moss to help lower it over time, but it just isn't working. I am getting nutrient lockout for sure. A lot of my leaves are pale yellow and surely aren't getting enough iron. I need a reasonably priced fix if anyone has it!
Thanks
Yeah, lime raises my pH when my pH is too low (I usually lime when my system average hits 6.2 or lower to take the system up to the 6.5-6.7 range). I use regular old peat moss to start my plants and then incorporate everything into my towers- the process of water dripping throught the plant roots and moss causes my pH to stay pretty stable but pretty low (usually aroun 6.4 or 6.5) compared to the pH of the water i add. this means i have to lime to keep the pH where I want it. if you're going to use vinegar, what Earl said is very important- use it with caution. buy a nice handheld pH meter (i use Testr3 meters) and mix small batches (say 20 gallons if you have a 200 gallon system) to the desired pH and let it rest for a while. If you come back to it and it's still at the right pH, then you have a primative rubric for figuring out what your entire system will require. then take your vinegar and add it incrementally(say 10% total vinegar required every other day for 20 days) over several days (or until your pH is getting close), testing your pH the whole way. make sure you are going slow and testing because in my experience, your system biology may cause your system reaction to vinegar additions to be pretty variable. and this can be very tricky- so i caution you to maybe try other options before vinegar. . .
THIS IS IMPORTANT: make sure you aren't reacting to diurnal effects of algae- as an algal dieoff, or shading could completely destroy your system once you've acidified your water, and thier regular diurnal effects would make your pH swings even more extreme for your fish/plants. I would shade the system heavily for a week or two before I started worrying about adding vinegar, and while i was shading i'd throw a bale of barley straw into your tank underneath your inflow (rinse it good first). In one system I had, I had my pH swinging from 7 in the morning to 10 in the afternoon- 100% because of algae.

Jeff Givan said:
Doesn't the lime make the PH higher? What kind of peat moss do you use in your towers? And, how much? For 4000 gallons what would you suggest if I use vinegar. I also need to figure something out to keep it that way, because when I add water it will be high again. I suppose that I could treat the water before I add it too the pond, the only problem is that I lose a lot during this time of the year due to evaporation and some leakage so I would need to premix it in a large vessel before adding.

Nate Storey said:
I have used pine needles, barley straw, and vinegar (cheap, but be very very careful), and all of them work. but now, with water dripping through the small pockets of peat in my towers, my pH stays naturally very low, even with slightly basic water- I lime on a regular basis.

Jeff Givan said:
Hey folks, anyone got any great and inexpensive ideas on lowering the ph in my pond. As I have said in the past our tap water is very high in PH. I just tested my pond again and it is still in the 9.0 area. In the past I have bought some PH lowering acid, but it is very expensive and with about 4000 gallons it won't be cheap to keep it in range. I have tried adding some spagnum peat moss to help lower it over time, but it just isn't working. I am getting nutrient lockout for sure. A lot of my leaves are pale yellow and surely aren't getting enough iron. I need a reasonably priced fix if anyone has it!
Thanks
I should say too- if your system is carbonate buffered, the addition of acid will slowly dissolve that carbonate buffer, so once all of your system carbonate has been dissolved, you run the risk of having your pH drop very suddenly with a very small acid addition. Another reason I don't like using vinegar unless i really have to.

Nate Storey said:
Yeah, lime raises my pH when my pH is too low (I usually lime when my system average hits 6.2 or lower to take the system up to the 6.5-6.7 range). I use regular old peat moss to start my plants and then incorporate everything into my towers- the process of water dripping throught the plant roots and moss causes my pH to stay pretty stable but pretty low (usually aroun 6.4 or 6.5) compared to the pH of the water i add. this means i have to lime to keep the pH where I want it. if you're going to use vinegar, what Earl said is very important- use it with caution. buy a nice handheld pH meter (i use Testr3 meters) and mix small batches (say 20 gallons if you have a 200 gallon system) to the desired pH and let it rest for a while. If you come back to it and it's still at the right pH, then you have a primative rubric for figuring out what your entire system will require. then take your vinegar and add it incrementally(say 10% total vinegar required every other day for 20 days) over several days (or until your pH is getting close), testing your pH the whole way. make sure you are going slow and testing because in my experience, your system biology may cause your system reaction to vinegar additions to be pretty variable. and this can be very tricky- so i caution you to maybe try other options before vinegar. . .
THIS IS IMPORTANT: make sure you aren't reacting to diurnal effects of algae- as an algal dieoff, or shading could completely destroy your system once you've acidified your water, and thier regular diurnal effects would make your pH swings even more extreme for your fish/plants. I would shade the system heavily for a week or two before I started worrying about adding vinegar, and while i was shading i'd throw a bale of barley straw into your tank underneath your inflow (rinse it good first). In one system I had, I had my pH swinging from 7 in the morning to 10 in the afternoon- 100% because of algae.

Jeff Givan said:
Doesn't the lime make the PH higher? What kind of peat moss do you use in your towers? And, how much? For 4000 gallons what would you suggest if I use vinegar. I also need to figure something out to keep it that way, because when I add water it will be high again. I suppose that I could treat the water before I add it too the pond, the only problem is that I lose a lot during this time of the year due to evaporation and some leakage so I would need to premix it in a large vessel before adding.

Nate Storey said:
I have used pine needles, barley straw, and vinegar (cheap, but be very very careful), and all of them work. but now, with water dripping through the small pockets of peat in my towers, my pH stays naturally very low, even with slightly basic water- I lime on a regular basis.

Jeff Givan said:
Hey folks, anyone got any great and inexpensive ideas on lowering the ph in my pond. As I have said in the past our tap water is very high in PH. I just tested my pond again and it is still in the 9.0 area. In the past I have bought some PH lowering acid, but it is very expensive and with about 4000 gallons it won't be cheap to keep it in range. I have tried adding some spagnum peat moss to help lower it over time, but it just isn't working. I am getting nutrient lockout for sure. A lot of my leaves are pale yellow and surely aren't getting enough iron. I need a reasonably priced fix if anyone has it!
Thanks
Thanks for all your advice Earl and Nate! My system isn't buffered at all with any carbonate since our tap water is so high in PH. We pull our water out of either an aquafir or the American Channel which is a channel made of all concrete that brings water from the Colorado River depending on usage and time. If anything I need to constantly keep adding something to control the akalinity. I do have a bit of an algae bloom right now so I need to be sure and take an early morning test and then an afternoon test. The one I did this morning was around 10:30 am.
We are in the same boat, you and I- alkaline water with an algae bloom. Only difference for me is no sign of life in the GB. Let me know if you find a pH lowering agent that you like, and I'll do the same. I'm thinking I may have to seal the ferrocement pond in order to reduce the effect. I was hoping it would have lost it's blush of lime by now, but perhaps it never does...

Jeff Givan said:
Thanks for all your advice Earl and Nate! My system isn't buffered at all with any carbonate since our tap water is so high in PH. We pull our water out of either an aquafir or the American Channel which is a channel made of all concrete that brings water from the Colorado River depending on usage and time. If anything I need to constantly keep adding something to control the akalinity. I do have a bit of an algae bloom right now so I need to be sure and take an early morning test and then an afternoon test. The one I did this morning was around 10:30 am.
if you are going to seal it look into used billboard tarps they work really well and it keeps them out of a landfill

Shawn said:
We are in the same boat, you and I- alkaline water with an algae bloom. Only difference for me is no sign of life in the GB. Let me know if you find a pH lowering agent that you like, and I'll do the same. I'm thinking I may have to seal the ferrocement pond in order to reduce the effect. I was hoping it would have lost it's blush of lime by now, but perhaps it never does...

Jeff Givan said:
Thanks for all your advice Earl and Nate! My system isn't buffered at all with any carbonate since our tap water is so high in PH. We pull our water out of either an aquafir or the American Channel which is a channel made of all concrete that brings water from the Colorado River depending on usage and time. If anything I need to constantly keep adding something to control the akalinity. I do have a bit of an algae bloom right now so I need to be sure and take an early morning test and then an afternoon test. The one I did this morning was around 10:30 am.
I have tried to use acid to reduce the pH of a system with a major buffer in it. Didn't work. the best I could do with the acid was to bring the pH of my top up water down to the level at which the buffer naturally acted. For me that was 7.6 because the buffer is shells. So, if the cause of your high pH is really just the top up water, then I would heavily advise pre-treating the water and leaving it to stabilize with aeration before adding to the system.

If the cause of the high pH is something within the system (media or concrete) then you can only expect to keep the system as low as the buffer will naturally allow. Trying to force the pH lower using acid while you have a strong buffer in the system will simply cause pH bouncing with is worse than the high pH in the first place. If you have limestone as your media, you will probably want to switch it out. If it is concrete, then sealing it may be your option though for some reason I think over time it might be possible to stop the concrete from causing problems some other way though that might need to be dealt with in the construction process. Sorry I don't have much good advise about how to make the concrete pay nice with Aquaponics though.

I have planted cucumbers in peat pellets in my NFT pipes and some of those cucumber plants are producing while I've never managed to do very well with cucumbers in my system otherwise, apparently they need ample supply of iron at certain points in development and with my high pH, that usually doesn't happen.
I can see where peat could help bring pH down and I do know when I have a heavy fish load in summer and they are eating lots, my pH will naturally get a bit lower.

Definitely follow Nate's advise about shading out the algae before taking other steps to change pH.
That's a good tip, but we are lucky enough to live on an island (Hawaii) that does not allow billboards. There is a fish-safe sealer available at reasonable price from Home Depot, but I can't recall the name right now.

Earl ward said:
if you are going to seal it look into used billboard tarps they work really well and it keeps them out of a landfill

Jeff Givan said:
Thanks for all your advice Earl and Nate! My system isn't buffered at all with any carbonate since our tap water is so high in PH. We pull our water out of either an aquafir or the American Channel which is a channel made of all concrete that brings water from the Colorado River depending on usage and time. If anything I need to constantly keep adding something to control the akalinity.
Actually Jeff.. I'd say that your water is in fact highly "buffered"... with carbonates... the Colarado from memory.. and any aquifers... are drawing from limestone.... hence your pH of 9.0...

Alkalinity and hardness are often confused... your alkalinity is caused by "buffering".... and the "concrete" probably isn't helping...

And as TCL says... adding acid... isn't effective.... until ALL the carbonate buffer is used up... hence the lowering of pH, just to have it rebound...

Topping up with "buffered" source water just negates any addition of acid... adding acid to your top-up water will overtime have more effect... as essentially you are lowering the "buffering" capacity... rather than adding to it...

Dosing your tank and top-up water ... and the natural acidification due to nitrification... will, over time move your pH...

Shading your tank and dealing with your algael problem is a must do...
Thanks everyone for your input. My pond had been clear up until we had a power outage and my filter back flushed into the pond. It is beginning to clear up with some treatment with a microbial lift product. My pond is almost 4000 gallons and is over 25 feet long so it will be hard to shade it all, but much of it is shaded by a lemon tree. Sounds like I am going to have to get a 55 gallon drum or 2 to do the pre-treatment of the top off water! Ahhhh the joys of aquaponics! I guess every place to live has its +/-. Just like we have earthquakes and others have tornadoes, hurricanes or volcanoes!

RupertofOZ said:
Jeff Givan said:
Thanks for all your advice Earl and Nate! My system isn't buffered at all with any carbonate since our tap water is so high in PH. We pull our water out of either an aquafir or the American Channel which is a channel made of all concrete that brings water from the Colorado River depending on usage and time. If anything I need to constantly keep adding something to control the akalinity.
Actually Jeff.. I'd say that your water is in fact highly "buffered"... with carbonates... the Colarado from memory.. and any aquifers... are drawing from limestone.... hence your pH of 9.0...

Alkalinity and hardness are often confused... your alkalinity is caused by "buffering".... and the "concrete" probably isn't helping...

And as TCL says... adding acid... isn't effective.... until ALL the carbonate buffer is used up... hence the lowering of pH, just to have it rebound...

Topping up with "buffered" source water just negates any addition of acid... adding acid to your top-up water will overtime have more effect... as essentially you are lowering the "buffering" capacity... rather than adding to it...

Dosing your tank and top-up water ... and the natural acidification due to nitrification... will, over time move your pH...

Shading your tank and dealing with your algael problem is a must do...

Reply to Discussion

RSS

© 2021   Created by Sylvia Bernstein.   Powered by

Badges  |  Report an Issue  |  Terms of Service