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Hey guys my Gulper is in a tank with sand that is pushing the Ph to 7.6. Should he be ok or do I need to change the substrate out? thanks

Hi all,

cjam93 wrote:Hey guys my Gulper is in a tank with sand that is pushing the Ph to 7.6. Should he be ok or do I need to change the substrate out? thanks

We would need to know a little bit more than just pH.

I've never kept

Asterophysus batrachus

, but is this the right species?

Another assumption would be that your Gulper (

Asterophysus batrachus

) occurs only in "black water" conditions. Again some-one who has kept them may know that they come from "white water" rivers as well, and that water parameters are relatively unimportant.

I'll also assume that you don't know whether your sand contains an appreciable amount of limestone (possibly as shell fragments from beach sand etc)? 100% silica sand should be inert.

The real problem then is that pH is a ratio, it doesn't really tell that much about the water on its own. You really need to know the carbonate hardness (dKH) of the water and its electrical conductivity (as either microS or ppm TDS).

If you haven't got a dKH test kit then you can use conductivity (the total amount of dissolved salts) as an indicator of the water conditions .

Black-water is very low in dissolved salts, and will have a conductivity of less than 150 microS (100 ppm TDS). In water low in salts pH is likely to be variable and as we approach pure H2O basically meaningless. I like to keep soft water fish in water with low conductivity, and I don't worry too much about the pH (it is inherently unstable in soft water).

If you have appreciable carbonate buffering the conductivity will be much higher, and probably more than 500 microS.

A neutral salt like sodium chloride (NaCl) would raise conductivity, but not pH.

cheers Darrel

Yes that is the right one. I do not know to be honest what the hardness of my water is I will try to track down a test for it. The sand I am using is Quickrete Pool Filter Sand. It says it is silica sand, but I do not know if it is only silica or just mainly that. Thanks!

Hi all

cjam93 wrote: The sand I am using is Quickrete Pool Filter Sand. It says it is silica sand, but I do not know if it is only silica or just mainly that. Thanks!

If it says silica "pool filter sand" it should be 100% silica and it shouldn't effect pH.

If you can get a low range TDS meter (they are all really conductivity meters) it is useful bit of kit. I'm in the UK but I'm sure you can get a $50 dollar conductivity meter that will work accurately.

I like conductivity as a measurement, because you can just dip the meter in and can get an accurate and repeatable result.

Have a look at (<http://www.planetcatfish.com/forum/view ... hp?t=41899>).

cheers Darrel

Hi cjam93,

I am the original author of the thread which Darrel mentioned. I bought the conductivity meter which was mentioned at the end of that thread and I'll tell you a couple of things I found. First, I like the meter I chose (HI98129). Second, it is not the cheapest model available, it is a little bit higher quality. For that reason it costs more than the $50 models Darrel mentioned. I bought mine at Amazon.com for about $140 (Worth every penny). And finally, no matter which meter you buy, you'll need to buy several maintenance fluids: storage solution, cleaning solution, TDS calibration fluid, and pH calibration fluid (the latter if your meter can also measure pH - mine does). To save money on shipping, I recommend you buy everything at once. I made the mistake of not doing that, and I spent more on shipping by going back later to buy some of the fluids.

Cheers, Eric

Ok thanks guys! So the reason that I thought it was the sand is that I have 3 aquariums with pool filter sand in them. Two of them are a different brand of pool filter sand than the sand that is in the gulper tank. I use neutral regulator on them and all my tanks are 7.0 with the exception of the Gulper's tank. I did use the neutral regulator in his tank as well, but it does not drop in pH. I did a water change yesterday though and since then the pH is showing between 7.2 and 7.6.

I will have to remember the TDS meter when I get some extra cash haha thanks!

Hi all,

cjam93 wrote: I use neutral regulator on them and all my tanks are 7.0 with the exception of the Gulper's tank. I did use the neutral regulator in his tank as well, but it does not drop in pH. I did a water change yesterday though and since then the pH is showing between 7.2 and 7.6. I will have to remember the TDS meter when I get some extra cash haha thanks!

I wouldn't worry about the neutral regulator.

I'm not a great believer in chemicals that reduce, or buffer, pH. They will all add to the TDS, and for soft water fish I like a low TDS. If you have water with low TDS you can easily lower the pH with the tannins and humic acids from Alder cones or Indian Almond leaves etc.

It is easy to add things to "water" (really a dilute solution of various solutes with H2O as the solvent), but it is difficult to take them away. If we have hard water, and we want to keep soft-water fish, we really need to use RO or rain-water.

If we want to keep Tanganyikan fish, but have soft water, it is much easier we can add salts (NaHCO3, MgSO4.7H2O, CaCl etc) to increase conductivity, dKH and dGH

Buffers
If I use an "instant coffee" analogy it sort of explains why these don't really work. You start with water, add the coffee powder, your coffee is now dark and bitter, you add sugar, you add milk to make the coffee less dark and bitter etc. but what ever you add you can't go back to the water you started with.

So it is the same for buffers etc. everything you add takes you further away from the water you started with. A neutral buffer is something like a phosphate buffer where you can use differing proportions of NaH2PO4 (acid) and Na2HPO4 (base) to maintain a set pH.

The buffer or regulator works because you have a reservoir of buffer. If you go back to the cup of coffee, it is like having 4 spoonfuls of sugar, it can't all go into solution, you can't make the coffee any sweeter, but if you add more water some of the un-dissolved sugar will go into solution and maintain the sweetness.

cheers Darrel