Backyard Aquaponics
A place to discuss aquaponics

Did a Ph test of my tap water yesterday to find that the reason I am dealing with such high PH is that the city water has a PH of 8! Also tested some water that had gravel in it for 24 hrs to find that it didn't change the PH of the water. I have yet to test the PH of the water I have been getting from the RO machine at the grocery store. They are pulling water right from the city as well, so I assume there will be little difference.

Today I bought a PH down kit and wanted to run this by folks before using in case anyone has anything insightful as to how to administer it. I am obviously not going to put in a full dosage at once, but slowly work it in. Would it be best to put it in the GB, or directly into the FT? With this stuff, is there a chance of a big rebound back to its original PH?

Any suggestions/ personal experience stories would be more than welcomed!

Fish still look good, bought 7 more goldies today to replace the 3 I lost over the past 3 weeks. Plants.... no progress....

Our water out here seems to be about 8ish right out of the tap as well. After a year it dropped just fine and in the meantime I added supplementary nutes. You might test distilled water with your gravel, just to be sure of the gravel effects.

We've never used PH down except in our pool (and that is sodium bisulfate while yours may be HCl), but the trout seem to be happy. Whatever you add, it would be nice to find a way to add gradually. With drops you might add a drop every hour or so.

Our trout are surviving and doing well in a murky pool with PH swings of about .4 each day (but coming out this week). Since trout are surviving that, I'm sure your tough fish will do OK if you limit their PH change to under .5/day. Just make sure it is not in one jolt.

PH should not bounce back much unless your gravel is buffering.

Picked up some RO water from the store today and tested it. It measures 6.8-7, quite nice. Since this is what I have mostly been adding to my FT I figured it had to be the gravel. I soaked a hand full of the gravel in about 2 cups of water and within 2 hrs the PH of the water was up to 7.4! As I look back at the document I have about the gravel, I now read that it has limestone in it... Should have looked at that sooner!

So I think I will start looking into a new growing medium.

Since I don't want all of my fish to die while re-cycling new media I am looking at other options. Is it possible to begin bacteria growth in a GB by letting water with some humonia or fish emulsion sit stagnant in the GB. In other words, can I keep my current system running while having another GB cycling without being connected into the system and then switch the GBs out once the new media is cycled?

Just add the new growbed/media into the system... give it a week, then remove and replace the old media...

Rupe, Yeah I thought about splicing my pipe from the pump and adding on another GB to the system to get it cycled but space becomes a bit of an issue... That may prove to be the best way though... I'll have to ruminate on it for a bit...

i think that might be the best way, glad to know what the problem is.

The bacteria are often concentrated where water flows into the growbed. If you put 5% of that old gravel with 95% new you will be mostly cycled...

Seed-bacteria are most effective where water enters, so put old dirty gravel there.

Hydro: Good idea! What do you think about actually putting the old gravel in some sort of well drained container and than put it under the input? This way, once the new medium has cycled I can pull the whole container and replace with clay pellets.

That would work fine. Sorry to be so slow getting back to you....busy here lately.

Just ordered two 50L bags of Hyrdroton form the local Hydro store. I am going to be able to increase the depth of my GB to 10-11'' due to the clay balls being lighter then my current gravel. I will have about 74 L of medium and have just fashioned two 2L containers out of old water jugs to hold some cycled gravel to act as seed medium. 4L is about 5% of the new GB volume. As soon as the system gets reestablished I will remove the containers and gravel and replace with clay balls. Hopefully this solves my growing issues!

I was just reading in another thread that fish food you buy at the pet store may not contain all of the essential nutrients that your fish want, and that create high quality fish waste thus providing the nutrients your plants want. I am thinking that this may have been an issue with limited plant growth as well as i have been using the normal "goldfish flakes". Can any one suggest a better food for goldfish here in the states?

Got my Hydroton! Cleaned it this weekend and will hopefully be making the switch sometime this week!

I think I spoke to Rupert about this because I had the same concern.

I think as long as your fish food has high enough protein it will be OK (>30%). I was using the goldfish flakes in the orange container & it had a good amount of protein. I'm now trying something which is actually less expensive but a higher percentage of protein & everything seems fine. Check the ingredients. Fishy things are good - I think corn/wheat type of things not so good.

Some fish can digest vegetable protein, others (like trout) not.

Thanks for the feedback! Just checked and my food contains: Salmon, Black Cod, a "seafood mix", wheat flour, kelp and vitamins... So it seems like this one is ok.

Just put in the Hyrdoton!!!! I will post pictures and details later!

Alright, a quick update on the new grow medium.

Got two 50L bags of hydroton from the local hydroponics store (which I am NOT impressed with). Needed about 80 L to fill my grow bed to a depth of around 10-11", so I have a bit extra. That's ok though, it can always go towards my next larger system sometime in the future!

Gave it a good washin':



Pulled all of my gravel from my grow bed. Found 4 of the 5 earth worms I had put in there about 2 months ago and they were fat and happy! Once it was empty I gave it a good washing, changed the stand pipe height to 9" which makes it 1" below the surface of my growing media. Once that was all in place, I began to pour in hydroton. I have to say, this stuff is pretty fun to play with! It has a very satisfying feel to it.

The fact that I have fish already in the system complicated the matters a bit, as I didn't want to loose them all during a re-cycling of the GB. Going off to the brilliant advice given to me by Hydrophilia, I made 2 containers out of milk jugs to put some of the gravel in to act as a seed to get the new media cycled quicker. Hydro suggested too keep about 5% of the new media volume as the old gravel so I made 2 containers which hold 2 L of gravel apiece. These I positioned under the input piping and then filled up around them with hydroton.



My plan is that after a couple of weeks, when the bacteria has had a chance to establish itself in the hydroton, I will pull the gravel containers and replace them with more hydroton.

Measured my levels before changing media. PH:8.2, Ammonia: 0, Nitrite: 0, Nitrate: 0-5. A day later, after adding 5 gal of water the levels are PH: 7.5-7.8, Ammonia: 0, Nitrite: 0, Nitrate: 5-10. Lookin' good! Hopefully I wont get too much of an increase in Ammonia and Nitrites. I know my fish hope this as well!

I am going to wait to replant until I pull the gravel containers, and the media will shift when I do this.

Hope all is well in the land of AP!