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buynovsky
01/31/2002, 11:48 AM
I am having difficulty with my smaller reef tank....Things look better at the end of the week, right before I do a water change.....

Creatures all over the glass, Calupera growing 1/4" a day, anenomes in full bloom.... After I do a water change about 35% (with RO water-I know this is a lot but my nitrates get to 30-40ppm at the end of the week) everything goes in hiding for about 5 days, the anenomes shrink to 75% of normal, the calupera falls apart all over the tank, the algae all but dies. I was running the protein skimmer, but I found the tank looked worse when I ran it?? I've got a number of invertebrates and a ton of lava rock and bio medium in my filter..... I also do not run carbon.
I add CA twice a week and a trace element solution with my water change. I feed the anenomes twice a week a very small piece of silver sides, and brine shrimp every other day..and a sprilina disk every other day.



My paramenters are as follows.

PH 8.1-8.2
Temp 80-81F
Nitrites- 0
Amonium - 0
CA around 400
Salinity 1.021
Nitrates - 5ppm day of water change 30-40ppm end of week

So my questions are:

1. Dr. Ron said I needed Salinity to 1.025-.026, this seemed high as all the hydrometers and books say 1.021-1.023 would a .002 make a big difference?
2. Should I add more trace elements and turn the skimmer back on?
3.Should I feed less often an do more frequent water changes in smaller amounts?
4. I was thinking of setting up a plenum, is this good? and would this really disrupt a already set up tank?
5. Any other suggestions??


Thanks so much in advance!!!

Randy Holmes-Farley
01/31/2002, 12:56 PM
1. Dr. Ron said I needed Salinity to 1.025-.026, this seemed high as all the hydrometers and books say 1.021-1.023 would a .002 make a big difference?

Seawater has a specific gravity of about 1.026. Use that. There's no evidence that lower values are better. Forget the hogwash from hydrometer or salt mix manufacturers. Here's a link to my article on hydrometers if you are interested:

http://www.advancedaquarist.com/issues/jan2002/chemistry.htm


2. Should I add more trace elements and turn the skimmer back on?

I don't suspect that is the problem in this case.

.Should I feed less often an do more frequent water changes in smaller amounts?

Smaller water changes sounds good. Are you carefully matching salinity, pH, and temperature when you change the water? Are you stirring up a lot of crud when you change that much water? Do the corals get exposed to air?

Less feeding may or may not be beneficial overall.

I was thinking of setting up a plenum, is this good? and would this really disrupt a already set up tank?

Good as opposed to sand without a plenum? NO.

Good as opposed to bare bottom? Maybe helpful.

Any other suggestions??

When you say it looks worse right after a water change, is that 1 day later, 10 minutes later, or what?

buynovsky
01/31/2002, 01:14 PM
Thanks for you advice so far.

Here are the answers to your questions.

1. I don't stir up a ton of crud. There is about 1/8-1/4 of fine sand on the bottom. This is completely covered by lava rock, so I can NOT access it with my siphon. I just skim watter from the top part of the tank.
2. When I do a water change there is no change in water clarity, it is slightly clearer, but that is partly due to the fact that I scrap alage from the front glass. (I have some coraline algae on the glass, but mostly a very hard green algae which only comes off with a razor blade) and none of the corals are exposed to air
3. The water I remove is fairly yellow coloration
4. Typically the next day after the water change, the anenomes shrink, the bubble coral shrinks, the mushrooms shrink (all to about 75% of pre-water change size) and the calupera falls apart. I'm thinking that its a double edge sword, because the more nitrate and phosphates in the tank and the calupera flourishes as it eats them up, but the soft corals are put under stress.
5. I will slowly bring up the salinity to 1.026 (do you recommend that I get a refraction hydrometer or probe hydrometer?) I don't know how accurate those plastic ones are, after all salt deposits could form on them when they dry-I do flush with RO water as best as possible- and I hear that if you leave them submerged in salt water they will absorb salt and give a different reading.
6. So you would not recommend a plenum if I have a very shallow sand bed?
7. It just seems that the only thing that changes as the week progresses is the build up of organics, nitrates and phosphates....and this is when my tank comes alive??



Thanks in advance

Randy Holmes-Farley
01/31/2002, 01:48 PM
So you would not recommend a plenum if I have a very shallow sand bed?

Correct. A plenum under a thin sand bed would likely accomplish nothing.

It just seems that the only thing that changes as the week progresses is the build up of organics, nitrates and phosphates....and this is when my tank comes alive??

You didn't say so, but I assume that you are matching pH, salinity and temperature in the change? What salt mix are you using? It could be they like organics. Or that they don't like something coming in with the change.

. I will slowly bring up the salinity to 1.026 (do you recommend that I get a refraction hydrometer or probe hydrometer?) I don't know how accurate those plastic ones are, after all salt deposits could form on them when they dry-I do flush with RO water as best as possible- and I hear that if you leave them submerged in salt water they will absorb salt and give a different reading.

Anything is better than nothing. A conductivity probe (sometimes called a salinity probe) would be my choice, but many people use refractometers to good effect. Simple hydrometers can be erroneous, but will work. I go over the concerns in my article in the earlier post. The Tropic Marin glass hydrometer is a good choice, IMO.

tyoberg
01/31/2002, 04:43 PM
buynovsky,
more, but smaller waterchanges are easier on the inhabs.

lava rock--the purity and quality can vary greatly. a lot of it starts out it's life as ore of some kind and reaches your tank as a waste product of some foundry--also called slag. therefor, unless you are pretty sure of it's origins, it can easily contain a lot of heavy metals. It would be worth your while to test the tank for copper, as a minimum, before you continue your tank with it.

Ty