Problems with low pH

[sschofie]

Hello all, I have a 55 gal. FOWLR that has been setup for about 6 months now. My reading are as follows: Am: 0, Trite: 0, Trate: 5 (and dropping thanks to chaeto), Phos: .5, Alk: 12dkh, Calc: 400, SG: 1.026. I have 3 powerheads(one in each corner facing center of front wall and one in center of the back wall facing the front wall) with a total of 500gal/hr (I think this is too low). There is about 60 lbs. of live rock(Little low) and crushed coral substrate. My problem is that my pH readings are always at 7.7. I add the Seachem buffer to raise pH to 8.3, but within a few days it is back to 7.7. I think that it may be an aeration(sp?) problem since I do not have a Skimmer, but I'm not sure. My sump light runs 24hrs/day and my main light run from 9am to 10pm. Could someone please help me fix my pH problem. TIA

 

[lando]

A low Ph is better then a drastic change in Ph. Be very careful not to raise it too fast using chemicals. Do you have a glass top on your tank? If so, remove it if you can. Aim a powerhead toward the water line so it breaks the surface of the water. See if this helps. Water changes will help to slowly raise the PH and buffer the water as well.

 

[gooyferret]

Could be the salt mix that your using i have heard of people with that problem also.

 

[sschofie]

Thanks lando, I do not have a glass top on the tank. My powerheads are close to the surface and I have an external overflow. I think my surface aggitation is good(many ripples on surface). Do you have any other ideas on how to correct this?

 

[sschofie]

Thanks for the advice gooyferret, I'm using Instant Ocean salt mix. Is this ok?

 

[lando]

What are you using for a test kit?

 

[malkore]

IO salt never got me past 8.0 pH, Oceanic keeps me between 8.1 and 8.2 (depending on the time of day I test pH).

You're at least 50gph below the minimum recommended gph of 10 x per hour. Some people go up to 20 x per hour, so you definitely have some room for more circulation.

I wouldn't use a straight pH buffer, particularly when your alkalinity is already in a good place...you should have plenty of buffer already...so something is lowering pH - CO2, decomposing organics...something.

 

[sschofie]

lando - My Alk and pH test kits are from Tropic Marin and my Trate and Phos kits are Nutrafin(sp?).

malkore - I do realize that I'm under my gph for circulation and plan on upgrading soon. I also thought that CO2 might be my problem, but I thought the chaeto would fix that if it was the problem. I'll try the Oceanic salt for a while to see if that helps. I guess it could be decomposing organics since I have a CC substrate and I never siphon it out. Wish I went the sand route, but it's a lil too late now.

Thank you for all of your help.

 

[quarryshark]

One way to tell is to mix up a bucket of the IO, airate it for a day and test the PH. If its low, then there is your problem. If it is within normal limits, then then do a couple of large water changes ans see if that helps.