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My first saltwater tank - Aqueon Frameless Cube Aquarium, 3 Gallon

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Fish Crazy
Mar 1, 2023
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Houston, TX
Planning on corals but not sure what kind yet. Currently cycling the tank. Just bought new full spectrum light should be here tomorrow.


Aqueon Frameless Cube Aquarium, 3 Gallon
Imagitarium Pacific Ocean Water, 5 gallons
CaribSea Aragalive Live Reef Sand
CaribSea LifeRock FragZone rock structure (Used Fluval Sea Aquatic Epoxy Stick to put together)
YukiHalu Small Submersible Aquarium Heater, Adjustable Mini Fish Tank Heater 25W
CHERLAM Aquarium Surface Protein Skimmer,3W Fish Tank Protein Skimmer,3 in 1 Aquarium Oil Skimmer for Sea and Fresh Water
Fluval SEA Marine Nano LED Aquarium Lighting with Bluetooth, 20 Watts,Glass

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small tanks are harder to maintain so go for soft corals or coral morphs, and avoid hard corals.
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Yes, perhaps a snail or something small. I don't think the tank is big enough for fish.
Yes I agree it is to small for fish I have always wanted to try a saltwater tank, maybe someday. Maybe a saltwater hermit crab. It says for 2 you need 5 gallons but with 1 think 3 gallons would be fine.
pH is too low. It needs to be 8.5
I was browsing some coral water pH needs yesterday and most were between 8.3 to 8.5 pH.

I was wondering if there is a correlation to the lower pH the tank has now and the cycle. Some of what I read said that to just wait until the cycle is done before trying to get pH stable. I also have only been doing water top offs during the cycle, no water changes. So not sure if that will raise it once I do a water change.

EDIT: Had to know, so I tested source saltwater and it is at 8.4 ppm pH. So, pretty sure if I do a water change with the source my pH will go up to where it should be. The question still remains, should I do this while it is still cycling?
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So I did do a water change to get salinity levels back up as they had slightly shifted lower due to the top offs. That didn't seem to affect the pH all that much. I just added 0.5ml of Seachem Reef Carbonate and going to see what the pH shows in a bit. If that doesn't get it up there I might have to switch to using the Seachem Reef Buffer product.
So I did do a water change to get salinity levels back up as they had slightly shifted lower due to the top offs.
Neat little project! I love my marine tank! Mine is a bit larger at 160L (42gal) which has helped me with a bit of stability at that size. I'm considering adding an automatic water change system to mine. I would think with a really small tank like that you could essentially do that alone to maintain your parameters. I think Matthew's new setup on BRS is done that way, if I recall. Regardless of what you do, I'm interested to see how all come out. Thanks for sharing!
I added another 0.5ml Seachem Reef Carbonate to get levels to correct number. Parameters are perfect now looks like. And cycle pretty much complete too.

Salinity 35 ppt
pH 8.4
Calcium 400 ppm
KH 161.1 ppm
Phosphate 0 ppm
Ammonia 0 ppm
Nitrite 0 ppm
Nitrate 5 ppm
If the cycling process stalls, you can do a big water change and it usually gets it going again. However, this is more of an issue in freshwater tanks where the KH (carbonate hardness) drops. The KH is unlikely to drop in a marine tank that has limestone in.

A coverglass will help reduce evaporation and provide a much more stable environment for the livestock. It will also help trap heat and reduce your ower bill.

If you use artificial marine salts, you need to make the water u 24 hours before you use it so all the mineral salts can dissolve completely.

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