Fixing PH swing..any suggestions

mhornsby858 · #1 01/12/2005, 01:19 PM

I have been monitoring the PH in my tank with a Pinpoint PH monitor and noticed the usual PH swings 7.83 - 8.1 that happen as desribed in multiple articles through out the day and night. I pumped in fresh air that fed near the skimmer air intake and the PH went up to 8.28 which is way better. However during the night when the pump was off due to rain PH went back to 7.86. Pump is back on and its slowly rising.

Other readings: salinity 36 - 37 ppm ALK 9.4 dkh Calcium 520 ppm (Oceanic salt) also have been doing 5 - 8 % water changes every three days, had a nitrate spike (25 ppm) 5 days ago which is now under control at 2.5 ppm.

Plan of attack: I have been planning, and now pushing it into the fire, a refugium, light cycle opposite of display. I have been thinking though of a refugium divide into two different substrates: 40 lbs of Oolitic sand (which is more like 20 - 30 lbs when washed) maybe with a plennum I don't think I had enough sand when started tank it covered 2.5" - 3.0" and now had compacted to 1 - 1.5" in just 8 months and either live sand mixed with live rock rubble or that "mud" My main goal is to balance PH and remove nitrates.

A couple of questions on this: Putting new sand into a system, is that going to upset the nitrogen cycle? I am sold on Oolitic sand but I also want to have one other type of substrate to provide more filtering especially with nitrates? Should I track down and find real "live sand" that has been established already in a tank or start from scratch? Also the book of Coral Propogation mentioned using cured live rock rubble quite a bit of it to make a filtering device to remove nitrates, it said the rubble would have greater surface area and could be stacked on top of live sand and arranged in the refugium so that water would move around easily. This is where I am getting confused. I Could use some professional advice on how to proceed.

Also I have just set up a surge device so my current and water flow is optimal.

Randy Holmes-Farley · #2 01/12/2005, 02:24 PM

I think a refugium growing macroalgae is desirable in a number of ways, but it sounds like the pump alone will be able to handle the pH concern?

You might leave the sand out of the refugium. I have it in mine (oolitic and a small amount of live sand), but I don't think it does anything useful, and for a future tank I won't have it. My macroalgae takes up the nitrate.

mhornsby858 · #3 01/12/2005, 08:59 PM

So just getting fresh air into the skimmer would correct that PH swing?

In the refugium would live rock rubble be a good substrate and then macroalgae gowing above it? Or is that over kill and just have macroalgae?

mhornsby858 · #4 01/13/2005, 12:19 AM

Do you know of any airpumps that are weather proof and are high volume or and air pump that would pull air in from the outside?

mhornsby858 · #5 01/13/2005, 12:49 AM

Also, I have a super reef devil skimmer and with the venturi valve I understand how it pulls air into the chamber but could it work if more air was forced into the air intake for the skimmer or would that mess up the venturi process and decrease the effectivness of the skimmer. Thought being if I had a strong air pump I could ram fresh air in to the skimmer. Right now the fresh air tube exits above the intake of the skimmer. I think more fresh air would get into the skimmer if I forced more air in.

Any thoughts?

mhornsby858 · #6 01/13/2005, 01:22 AM

Sorry Randy, one more question about the fugium. My protein skimmer runs pretty good, I have a micron filter catch that the output goes into to take out the micro fine bubbles and I notice this filter trap gets dirty pretty quickly with brown green stuff almost like the stuff in the skimmer. I change it frequently to help reduce nitrates and not affect the nitro-cycle. Normally people have their skimmer output sent back to the sump. What exactly is that "waste" coming out of the skimmer being collected in the micron and if its nutrients, could it work if the output was put into the fugium w/ LR rubble and macroalgae that could benefit and use it to filter it out so I can get rid of using the micron filter. I want to minimize the amount of "nitrate bottlenecks" or factories that other people call it and maintaince/costs. So my unltimate plan is to only have one sponge pre-filter to wash or replace for big particles and leave the rest of the filtering to the skimmer and fugium, organic filtering.

So linear outline of flow: Pre-filter overflow -> sump -> skimmer -> fugium -> sump -> return w/ (breaks to ROWA Phos reactor) -> surge -> tank

Randy Holmes-Farley · #7 01/13/2005, 09:06 AM

So just getting fresh air into the skimmer would correct that PH swing?

I think that you need to think of this as raising the low pH, not in "correcting the pH swing" which is a different concern. Fresher air to a skimmer may help. Limewater would likely be a bigger help. This article has details:

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

In the refugium would live rock rubble be a good substrate and then macroalgae gowing above it? Or is that over kill and just have macroalgae?

I do not think that you need any substrate for this purpose, but live rock rubble is fine, IMO.

Do you know of any airpumps that are weather proof and are high volume or and air pump that would pull air in from the outside?

No, but I expect there are some.

[pB]I think more fresh air would get into the skimmer if I forced more air in.[/B]

Forcing it into the vicinity of the skimmer inlet is certainly desirable. Such as pumping out fresh air 1/4 inch from the inlet. Whether actually connecting and forcing the air in is beneficial may only be clear after trying it.

What exactly is that "waste" coming out of the skimmer being collected in the micron and if its nutrients, could it work if the output was put into the fugium w/ LR rubble and macroalgae that could benefit and use it to filter it out so I can get rid of using the micron filter.

Redirecting the stream into the refugium may or may not be beneficial with respect to those solids. Removing them is best, but I understand the problem of them collecting and decaying. But if they just get dumped into the refugium, where do they ultimately end up? They probably still decay somewhere, just out of site on the bottom of the rubble.

mhornsby858 · #8 01/13/2005, 02:41 PM

What creatures would eat those solids? Snails, hermits,...? In other tanks that do not have collection methods for that left over solids how is it processed in the eccosystem?

Randy Holmes-Farley · #9 01/13/2005, 02:51 PM

They might get eaten and recycled again as crab poop. They might also just sit and be consumed by bacteria. It's a bit of a faw in the argument (or at least the understanding of the process) that mechanical filters cause nitrate as it implies that if not caught, that it disappears some other way, completely. In some cases, it might. In others, it may not.

mhornsby858 · #10 01/14/2005, 01:30 PM

For growing macroalgae what spectrum of lights do I want? LFS said 10K ICE White? What specturm benefits macroalgae best?

Randy Holmes-Farley · #11 01/14/2005, 02:15 PM

I don't think there have been careful studies of what type of lighting is best. IME, incandescent track lighting works better than fluorescents (although that may be a temperature issue more than light).

The details are in this thread:

http://archive.reefcentral.com/forum...hreadid=216369

mhornsby858 · #12 01/15/2005, 03:16 AM

Ordered a 9" x 6" twin pc 6,400k Light for the fuge should do well. In that article you mentiomed "chaeto" is that a good one?

After a conversasion with a local reefer he convinced me to cut back on the live rock rubble which is mainly attacking nitrites and not nitrate he said go with the plennum plan 3/4" to 1" and 4" - 5" of oolitic sand above it with the macroalgae on top of that with some LR rubble to transfer organzims to the oolite to get it started faster. Whats a good mesh material to hold the oolitic sand above the eggcrate (plennum)?

One question what does that miracle "mud" substrate do and why are many people are talk it?

Randy Holmes-Farley · #13 01/15/2005, 01:19 PM

Chaetomorpha is one of the best macroalgae for a refugiuum, yes.

I don't think a plenum is necessary or beneficial. I'd leave out the sand entirely. The growing macroalgae will take up the nitrogen that you are thinking the sand bed will be necessary for.

If you run for a few months, and can't get nitrate down, then maybe look to adding sand.

The mud is a substrate. It may also release nutrients such as iron. I don't generally think it necessary. I add iron as an independent supplement.