Ph test on frag plugs

[coral88]

I placed ceramic frag plugs in about 5 cups of water and let them sit about an hour. I did this first in R/O and then in salt water. The ph of the R/O was not changed. After repeating the test twice with saltwater the PH started at 8 and dropped to 7.7. Has anyone had problems or heard of ceramic plugs dropping the ph?

 

[Russellaqua]

The addition of any frag plug other than plastic will lower your pH some. The ceramic types are made from kaolinite clay generally. Once fired the clay becomes glass-like. However, the free ions in the water can weather this material and cause CO2 to be expelled into the water, lowering the pH by forming carbonic acid. This is a gross simplification of what is in fact a very complex process, but it gets the idea across. Because RO is so pure there is little to react with the plug, thus the pH remains more stable. In RO the only ion that could react with the plug is H, and this would release CO2 as well. However, due to processes that occur after CO2 liberation the pH would remain unaffected.

 

[coral88]

The addition of any frag plug other than plastic will lower your pH some. The ceramic types are made from kaolinite clay generally. Once fired the clay becomes glass-like. However, the free ions in the water can weather this material and cause CO2 to be expelled into the water, lowering the pH by forming carbonic acid. This is a gross simplification of what is in fact a very complex process, but it gets the idea across. Because RO is so pure there is little to react with the plug, thus the pH remains more stable. In RO the only ion that could react with the plug is H, and this would release CO2 as well. However, due to processes that occur after CO2 liberation the pH would remain unaffected.

I can appreciate your scientific knowledge, but you’re wrong. Marble frag tile will buffer R/O to 8 and I’ve tested cement/aragonite that took it to 10.5. A lfs was selling them and telling me they were cured. So no all frag plugs to not drop ph. Most do the opposite.

 

[gooch Verified Sponsor]

OK, now take 5 cups of saltwater and let it sit with nothing in it for the same time and then test the PH.

My guess is there will be a similar drop. Maybe not. But when I use to turn off the lights on my big tank I usually see a drop of about a half point on the PH meter. 8.3 to 7.8. I didn't use reverse photo period. It was like this before I used ceramic and after I started using ceramic.

We have been using ceramic in our systems for over three years and have never had an issue with PH.

The tank I have right now is 100% ceramic and we have no ph issues. Been running for only a few months. It is a 12 gallon aquapod with 9.5 gallons of water. Previous to that I had 120 gallon system 100% ceramic for over a year. I took that down only because I had a fire in the house and decided to take a break. I also had a 150 gallon system that was 50% ceramic with no issues.

One of my wholesalers makes 150 + frags at a time with no issues. Another wholesaler told me one of his stores at times will make up to 500 frags at one time. There are quite a few large scale operations that use our ceramic plugs and have been using them for years as well.

If there would be serious issues we would have heard about them years ago.

Curious, how many plugs did you place in that five cups of water? Was the ceramic dry when you put them in or wet. If wet with RO water what was the PH of the RO water. The water absorbed into the plugs could very well lower the ph as well. I think we need more information. I don't have a PH probe handy or any RO water. But I will get some and run a similar test in teh next couple days. Gotta order a PH meter and probe first. If you want to get a true test of what will happen you need to place as many plugs as you plan on using in the same volume of water you plan on putting it into. Putting 25 or 50 plugs into five cups of water may give you skewed numbers. Put that same amount into 150 gallons of water and it would probably be a blip.

 

[coral88]

That was the control and the ph is the same 8

 

[coral88]

2 hours PH is now at 7.4

 

[Russellaqua]

I should have said all ceramic plugs should lower pH due to the chemical reactions. Aragocrete is extremely alkaline and will raise pH. This is why getting wet cement on yourself can be dangerous as it can cause chemical burns. Marble frag tile is made out of calcite, a polymorph of the aragonite that coral skeletons are made of. It's not really a manufactured product but rather a mined product cut into pieces. It'll have essentially zero effect on a coral tank. My guess is that the amount of water in comparison to the amount of plugs is so overwhelming that the effect on overall tank pH is minimal. pH is a logarithmic scale so it requires a lot of reactions to make a small change up near pH 8.

 

[coral88]

3 hours ph is now at somewhere just over 7. So all ceramic plug drop ph. Is it not better for the substrate that coral is grown on to have a higher ph. Or be neutral. I would think even if the plug had no great effect on the water it would not be good for the water in-between the coral and the plug.

Thank you for the replies please keep em coming.

 

[Russellaqua]

I'd say the ceramic plugs are good. People have used them successfully. You could use aragocrete, which has the opposite problem. The most natural way would be to use marble, as this is essentially what corals grow on in the wild (marble is the metamorphic form of limestone, the rock coral becomes.) They all seem to work quite well. In the end I think it's up to what you find the easiest to use, and what you can get most cost effectively.

 

[BeakerBob]

If you set a cup of RO water out and measure the pH right away, the let it sit for a several hours, the pH will change as it sits due to increased absorbance of ambient CO2, especially in a closed house. The CO2 will slowly drive the pH downwards until it reaches equalibrium.

 

[gooch Verified Sponsor]

Again how many plugs are you using for your five cups of water? This test really says nothing unless you are keeping a five cup frag tank with xx amount of frags in it. It only proves that in your test x amount of plugs in five cups of water lowered the PH. I need more information. Run your test with the same amount of water in your system.

Wet plugs or dry? Did they absorbe ro water first?

Also put some in your tank for a day and then run your test again. Put it in your tank for a week and then test it again. Put it in your tank again and test them a month later. Just curious. They can be used right out of the bag with no ill effects, I have mounted corals to them straight out of the kiln. That doesn't mean they don't age or go through a cycle. Not only do most of my customers prefer our plugs to aragonite or plastic. Many claim better growth rate in side by side tests. Although that is also a test that is hard to prove to be fair to the other plug makers. We've never looked at PH because it has never been an issue. I had a PH monitor on my tank 24/7 and it just was never an issue, I didn't see the same thing you see in your five cups of water. I still do not think it is. There are thousands and thousands of frags out there on our plugs. They do what they are designed to do and they do it well. So are you telling me that the people that mount corals to other plugs like plastic or uncured(cured) concrete plugs that can burn the coral are better off? I used plastic, concrete and just about every other media I could come up with to propagate corals. I tested the ceramic for over a year before I ever made a single plug for anyone. In my ten years in the hobby I still believe the ceramic is the best media I have found. If I didn't truly believe that I wouldn't waste my time making them. If I was in it for the money I would find something better to focus my efforts on. I make them for the hobby, to further aquaculture. I don't push my plugs on anyone and actually turn away almost as much business as I take in.


I know of one really large coral farm that suffered many losses using aragonite plugs even after curing them for 60 days. Now I can not tell you who they are and I think they still use the same plugs but they cure them even longer now. We are negotiating with them in hopes to put our plugs in their farm. It probably won't happen. I can't touch the price of the aragonite plugs, but you never know.

Again answer the rest of the questions please in my original post so I can run the same test you run.

I am also going to one of the shops that uses my plugs for his corals this weekend. I will be sure to take lots of pictures. I asked him if he saw the issues you are seeing. He has been using them as long as I have with no issues either, before I ever made them available for sale. He even told me his buddy has six hundred plus frags going on our plugs with no issues either. If I can get over there I will shoot some pics there too. I will be at the Ohio frag swap this weekend to touch base with another vendor using our products. I will ask him too. He has been using our products from the very start as well.

 

[Russellaqua]

The pH of pure water in reaction with the current atmospheric pressure of CO2 will result in water of pH 5.4 theoretically. I suspect the plugs would contribute only minimally to this lowering of pH.

 

[coral88]

I will do more test. But Saying the water will change on it’s own and the frag plugs have very little effect is hard to believe because I have the very same container sitting next to the one with the plugs and the ph has not moved. The reason I tested in such a small amount of water is because I wanted to know if the plugs could have any effect on ph. I really didn’t expect them to do anything. The plugs that went into saltwater were rinsed in the same saltwater right out of the bag.

I DO NOT THINK CERAMIC FRAG PLUGS ARE A BAD PRODUCT AND WILL MORE THAN LIKELY BE USING THEM IN MY PROPAGATION TANKS.

 

[coral88]

After a week in my sump I retested the plugs and they are not having any effect on ph. Also the 30 or so frags I glued to ceramic plugs are doing great.