Backyard Aquaponics
A place to discuss aquaponics

How did I not notice a need for a "go to" in there?
Note to self: write "always re-read before posting!" one-hundred times.

0 to .5ppm nitrites? Hmmm...your nitrites got down to zero when cycling with ammonia, but popped up when you added the fish: maybe your bacteria just need another week or so, especially if you keep changing water to keep levels really low.

I really think the 11 minnows are too much fish for the 10 gallon tank and my two small growbeds. The fish have stopped congregating at the terra cotta pot so maybe one was spawning? I do not see any little ones so I figure they were eaten. Since they're not using the internal space of the soda/water bottle caves, I'm going to remove that and put in spawning mops, this should also give me more surface area for more bioactivity which the system still needs according to the non-zero nitrites.

I've always had a few issues with the first growbed's bell siphon simply because of the slow water flow. Tried 4 or 5 different siphon pipes that all work great until they build up the slime bacteria level , and this past week changed to a single, then doubleloop autosiphon. The loop would drain great and then just dribble instead of stopping until I intervened. Yesterday I finally came up with an idea that works. I plugged up the drain hole, added a no holes overflow to the 2nd growbed which has a mini floating outlet. I also put the water tubing into the 2nd growbed so there's no chance of the 1st growbed overflowing since it now only has gravel, plants, and an overflow. The water fluctuation is a lot less due to the lowest level of pvc on the overflow but it works for about an inch of fluctuation.

On another note, I've been feeding flake and dog food pellets for variety. Over the past week I've noticed the tank water slowly becoming more brown. I attribute this to the dog food. Will a mechanical filter (which I need anyway to handle other waste better) remove the brown tint from the water? BTW: the other waste is slowing making its way through the pumps and growbeds, it is visible now. Also, if you lift up a terracotta pot, you can see the pyramid of waste making it's way to the pump inlet

PS: The fish now eat duckweed when they see it, although they still take to it like a dog takes to a grape, one fish gets it, then after a second spits it out, and it gets a tour of about 4 or 5 fish mouths before actually being eaten. The duckweed isn't really growing in the external container or in a protected area of the fish tank so I'll probably run out before long.

Read just last week that grapes (onions too) are toxic to dogs:
http://www.snopes.com/critters/crusader/raisins.asp

Rule of thumb I've been spreading since hearing it from the report from UVI (http://ag.arizona.edu/azaqua/ista/ista6 ... n/p676.pdf) is that 60g to 100g of fish food per day is required to support 1 square meter of solid plants. Since your light levels are probably lower, you might figure on half that or even less: maybe 20g to 30g per square meter of plants.

Most folks I've seen have somewhat brown, but clear, AP water. Maybe a charcoal filter would remove it, but might remove some nutrients as well. I really don't know. There might be food dyes in the dog food...

Update:

The coffee mechanical filter was a bust (or should I say tear?). I changed it to using some of the poly batting I still have from the airlift filter that failed. The water is now clear again! The poly batting lets particles pass through so I'll change to brown paper bags when I get a chance to see how those hold up and if they'll . (Seems to work for the autopot guys.)

Lost the little guy this past weekend, aka "Watcher". Maybe the 0-.50 nitrite finally got to him? The day before that he just stayed near the surface in one corner. He appeared to be looking for food at the surface but didn't eat quickly when I put some near him. Maybe he was getting air? He wasn't frantic, but slow moving. One of the bigger fish stayed around him or kept checking on him until he died. A couple of the fish were really aggressive this weekend, maybe he got in a fight? Although research says minnows just push each other around, they don't have teeth. May have had too much stress because I took out the bottle caves and put in a spawning mop and a couple terracotta pots back in.

So now I'm at 9 fish. Guess I miscounted before, they usually move too quickly to get an accurate count when the light is on. One of the 2 ivy clippings is getting more leaves, and the other clipping has still only developed one or two new roots, and one or two new leaves since I put it in. The other sprouts are still, well, sprouts. Not much growth to report. Maybe too wet? The system now has one minigeyser pumping water to both growbeds which use a no holes overflow to connect them so the cycle time is longer. The other minigeyser is now fueling the mechanical filter. And the small 799 air pump is still blowing bubbles without a stone.

Well, I got worried that maybe my analog soil pH tester wasn't giving accurate readings and I got an API pH liquid test. My tank water is 7.6+ To make a long story short, I had to kill 5 fish because of this somehow.

I'd figure I'd start bringing the pH back down closer to 7. This may account for the sprouts still being sprouts after 2 months. Maybe also explain the lack of ability for the system to grow algae? So I added a little vinegar to the tank, or so I thought. I added 20ml to the 10 gallon tank. Maybe I should have added less?

The next morning, 5 fish were dead. In hindsight, the evening before, one fish was poking around the airlift biofilter I was trying (2nd attempt at one). It had been in the tank a week already. I figured maybe the fish was trying to spawn. Looking back now, maybe the fish was trying to get oxygen from the bubbles coming up in it. Had the fish been at the surface of the water it may have been more evident. But only one fish was doing that at the time.

Ammonia is 0 and nitrate around 20ish but the Nitrites are 1.0+? I added a tablespoon of salt and stuck in the portable battery powered air pump and stone. The remaining 4 fish seem okay at this point, they came around and became active again shortly after putting in the extra air pump and bubbles. At this moment, I'm repairing the 799 air pump so it functions as brand new again and will pump a stone. An internal air flapper had a hole in it so it was pushing out air through the intake and outtake. The silicone is drying as I type this. I'll put it on a stone and back in the tank tomorrow. I still attribute the nitrites to needing more growbed volume so maybe I'll change out some water until then. Good idea?

In addition, over the past week, the tank has been getting browner and I haven't fed dog pellets in two weeks now so that isn't the cause. Brown is developing on the insides of the growbeds and the inside back of the tank. Brown algae perhaps?

A paper bag mechanical filter didn't work too good once the bag glue comes apart at the bottom. Poly batting with rubber band holding it around something round works better. It cleaned up the water from the dog pellet brown but it isn't affecting this new brown.??

If the vinegar dropped the pH too fast, how does it directly relate to dissolved oxygen? Obviously DO was the main cause for the fish deaths. I thought DO was more related to temps??

DO is directly related to wtaer temp Thorn... but ammonia is related to water temp and pH...

The pH scale is logarythmic.. what's your pH since adding 20ml to your 40L...(10gall)???

Could be your pH change and water temp bumped your ammonia level to critical...


As to the "new" brown.... sounds like a bio-film buildup to me... nothing to worry about... in fact a good sign IMO.... your system is maturing...

My systems have typically been sitting at around 7.6, probably due to gravel chemistry, but plant grow madly. From what I've seen here on this forum, modifying chemistry is best done very gradually, if at all. Some folks have added a lemon (I've added a half to one system), perhaps figuring that it is a slow-leaching source that shouldn't harm anything. One problem you have is small water volume=large fluctuations in parameters with small changes in chemicals, so you might have to add a half kumquat to get the same effect. *grin*

10ml might, indeed, have been excessive.....my condolences...


It may only be me, but O2 deprivation can be hard to tell unless they are doing something obvious like gulping at the surface. When I switched my aquarium from indoor growbed to big outdoor growbed and much bigger pump (more bubbles!) the fish increased activity, feeding, and apparent health. They also went intentionally surfing in the bubbles: very amusing. I would say to take a rule of thumb minimum (lbs of fish per gal of gb) and half it or quarter it, at least until the system is a few months old and you know what the fish look like in good conditions. And it is always really hard when cycling: in another few weeks things will probably look much better (cross fingers).



Yep. It will slow cycling a bit, but keep fish healthier. You have to be just about cycled...

Um...I read a tablespoon of salt=18 grams and that 3ppt of salt in ten gallons is 114 grams: you might want more like 2ppt. I don't know about your fishes' sensitivity to salt, though, nor have I checked on your plants' salt tolerance....



I'll second ROZ: bacteria. Or brown algae...it's all good. Once your system stabilizes, just scrub it off the unsightly areas and let it get sucked into the growbeds..


I doubt ph reduction directly caused the deaths by reducing dissolved O2 in water. More likely that the ph reduction was a direct added stressor that pushed them over the edge. Or perhaps the acetic acid itself interfered with fish uptake of O2. Or perhaps the acetic acid or ph change caused the bacteria to absorb more O2 for some hours, starving the fish? I can speculate all night....

Yea, DO is strongly correlated to temps, also less related to other factors like salinity. I would pull out my O2 tester and check the chart and instructions, but I said "speculate" not "pull out charts".

Good luck with the remaining fish..

Last night I went ahead and covered the sides and back of the tank with foil to help with the brown. The silicone also dried and now the tiny pump is running an air stone again just fine. I don't plan on adding any more minnows so long as they can remain at 4. They're schooling fish ya know. The 4 got excited for their morning feeding when they saw me this morning so they're back to normal.

The 5 that died seemed to be the bigger fish. A side note I forgot to mention is that one of them had a cut on its stomach about 1/4 inch long! With internals starting to come out. Not sure what would have caused that at all. Maybe rubbing against a terracotta pot? The fish don't have teeth and are known to just push each other when they become aggressive. I wouldn't suspect the higher nitrite levels to kill that many at once, especially the bigger fish.

I plan on leaving the small pump to run an airstone to combat any algae using up the oxygen. Maybe not enough oxygen was getting into the water from the bubbling in the growbed (which is constant from the minigeyser air/water pumps)? I now realize that these minnows do not act frantically when they try to get more oxygen so gotta keep that in mind if I see them in the top inch of water for ANY reason beyond feeding.

Would 5ml of vinegar per week be good? I measured distilled water and that measures at the lowest pH reading (so probably lower). I measured my de-gassed tap water waiting to go in the tanks and that measured 7.4 or higher. Could be due to our limestone aquifer? I wouldn't mind leaving the system at the higher pH the fish were use to but the plants just weren't growing (and figured the higher pH is the cause). The water readings in the previous post were what was measured right after I removed the 5 dead fish. The ammonia has never been above 0 or the first other level since the tank was cycling without fish to begin with. Ammonia is getting converted without a problem but the nitrite conversion isn't keeping up. (growbed space?) I figure I still have nitrates because the plants aren't bigger yet.

The 4 left are still doing good. The nitrates have started to reduce to 5-10 so I guess the increasing ivy's and now 3 inch sprouts are taking nutrients. Nitrite is at .25 and ammonia always at 0. The fish are becoming more accustomed to eating the frozen oatmeal cubes (once they defrost and sink). I've only given them two and broke them up a little after they sunk. I shouldn't have to do that once they're use to eating them more. Plus it is good practice for them to scavenge off the bottom as well as floating flake at the top. That'll help prevent food decaying in the tank.

Oddly enough, the 7 day pyramid has only decayed very little. Only one or two little dimples in it at this point. I'm still adding vinegar to the system to bring the pH down but at a slower rate than originally. Still kinda up in the air as to whether it was the pH or decreased DO from the brown algae that killed the 5. Probably a combination of both that just happened at the same time.

The tank water cleared up quite a bit a day or two after covering it with the foil, although it is more difficult to see the fish since the whole tank is darker without a light directly over it. The fish seem to hide more in a back corner now too.

Update:

All water readings are now 0. Most of my sprouts have died, probably my fault for putting salt in the growbed for trace minerals, won't do that again. The two ivy clippings are doing great and growing and the new leaves are all dark green. I have one squash sprout someone gave me in the growbed and a couple of the older sprouts still hanging in there. I tried to feed more to bring nitrates up a little but the minnows refused to eat more.

The 7 day pyramid, still had a little bit of it left after 2 weeks, I threw it out. My pH is too high for these things to work. Apparently they are made of calcite and dissolve by buffering the system pH up. But since my pH is already high (7.6+), it is useless and won't work fast enough.

I'm now planning to slowly change over the water from tap to rain and change over the limestone gravel to maybe Hygromite. They say it is pH neutral and works better than hydroton. It cost more than hydroton but not double. They say that it contains trace minerals as well. Now to save up some spare money for it.

The poly batting filter still works pretty good. I change out the material about once a week or more when it is needed. The minigeyser doesn't suck off the bottom enough to get everything so the other day I manually cleaned out a lot of the tank with a fish net and removed the spawning mop. The fish did not really hide behind it and don't spawn using that method anyhow. I just hope it didn't contain the bulk of bacteria that recently made my readings hit zero. The growbeds are still in place so we'll see how the readings are soon enough.

Hi Thorn

Sounds like your system has cycled for you

the change of your growbed media will help with your ph problem .. but you might considernot removing all of it and leave a layer in the bottom of 1 or all of your growbeds as a ph buffer so you dont have the problem that i have with a ph that was sitting high and is now dropping due to the age of the system and that there is starting to be a build up in the bottom of my fish tank of crap
( will be cleaning that out shortly and will also be changing the return flow into the tank to get the stuff of the bottom )

oh and some pictures would be nice too everyone loves pictures

The next level readings I took were .5 nitrite, 5 nitrate, high pH as usual, and about .2 ammonia. So maybe the spawning mop was doing some of the conversion before. I need to take readings again soon since the below changes.

Hopefully I can get more pics next month with a new camera. I cleaned out the growbed with 6 bottles as all but two pepper sprouts had died from those. Looked like one bottle had mold in the bottom, all black. I filled it back up with aerolite that I forgot I had and stuck in the two peppers which have since died. Guess they didn't like being transplanted. Threw in a bag of green beans and spinach or something, I forget what exactly at the moment, maybe parsley. The beans are coming out of their shell (less than a week) and half of them have floated their way to the top, heh. The aerolite is lightweight but doesn't completely float. We'll see how it goes.

I left the 2nd growbed alone with limestone gravel still in it until the bacteria builds up in the 1st growbed and readings level off again. I'm using the old spawning mop to help transfer bacteria. Had one end in the limestone gravel for a week and now it's over in the aerolite.

I was thinking of changing the 2nd growbed to yarn. It sinks once it has soaked up water a couple days and for small leafy veggies, it should be okay, right? It definitely has a lot of surface area. Or will it keep the roots too wet? (the yarn is 100% poly or equivalent)

A few questions about your system.
Are the grow beds flood and drain? or are they constantly flooded? If the light levels for the plants are kinda low, many plants just won't do very well and if you go using very wet media in a constantly flooded bed, and only minimal light, things will tend to rot.

I spent most of my first year with my system pH being between 7.6 and 8+. I think one of the keys to getting good plant growth with a young system and higher pH is to supplement with seaweed extract and iron. I was certainly able to see improvement of growth in my system when the plants have more balanced nutrients. Now that my system is gaining maturity, the pH is dropping and I'll probably need to buffer some more if it keeps dropping.

The grow beds are flood and drain. One bed has a homemade flout, which also drives the other bed now with a no holes overflow (both directions). So there's no chance of the 2nd bed overflowing, even if the overflow fails. The u-bend at the bottom of the 2nd bed for the overflow keeps about an inch of water at the bottom of that one.

Since I recently changed the first growbed to aerolite, I planted a package of beans and a package of spinach I think it was. The beans are still slowly growing every day (not at normal ap speed though) and the spinach hasn't shown itself after a month. And I still only have 2 remaining whatever sprouts in the 2nd growbed. They've been sprouts so long, I forgot what they were. The transplanted squash (from dirt) seedling/sprout eventually died.

On an odd and sad note, I lost one of the little guys. Found him on the floor when I got home from work the other day. The remaining 3 are still doing just fine. I haven't taken readings yet. There have been no changes in the system over the past month since the growbed change. Maybe he saw a fly pass by and 'went for it'? At any rate, I'm keeping the water in the tank a little lower now. Never would have thought I would have needed netting to keep the fish in the tank, indoors.

I still need to change the 2nd growbed from limestone to complete the change to get the pH where it needs to be. We got a new camera and wouldn't you know it, less than a week later, I find my old camera that has been missing for months! So it'll be easier for me take pics when I quit feeling lazy.