How to keep good Alk Stability in a 20 gallon Reef

[bkayereefs]

Hello guys!! I just wanted to inquire about a real problem I just realized I may have. So, to begin, I have a 20 gallon tank, stocked with 2 hammers, a fathead torch, an acan, a variety of mushrooms, and some gsp, not sure if thats considered mixed but thats besides the point. Anyways, I use the RedSea Coral Pro mix (purple bucket) which is rated at 12dkh and do about a 20% change once a week. Whenever I test (probably once a month) I test about 2 days after water change and notice I sit around an 8-9ish in Alk, and im aware corals are consuming. If the the salt mix is rated for 12dkh am I basically shocking the corals with a rapid raise of Alk each week? All my corals almost seem to be just making it by, they don't look like they are thriving but don't look like they are on the verge of death, so it's not very rewarding putting in the work I do each week haha. Any help/input on this issue would be so much appreciated. Thanks!!!!

 

[Rhetoric]

Hello fellow 20-gallon aquarists,

A quick suggestion: it’s time to learn a bit more about what your aquarium is actually consuming. The best way to do that is through consistent testing. Track your results and watch how the numbers change over time.

Try testing alkalinity daily for a week (or every couple of days if that’s more realistic), without doing any water changes during that period. For example, note where your alkalinity starts on Monday and where it ends on Sunday.

Once you establish how much your tank is naturally consuming, you’ll have real data to work with. Until then, I wouldn’t recommend dosing any alkalinity additives.

Once you have those results, I’d be happy to help further.

Also, here’s a couple photos of my 20-gallon for fun—and maybe a little street cred. LOL

 

[Jonify]

Hi! I think this isn't a big issue. If your corals aren't thriving, I don't think it's your salt. Sure, you could use something with a record of success like Red Sea Blu Bucket (more closely mirrors the chemistry your tank is likely to fall into), but even with RS Coral Pro, 5 gallon changes aren't likely to negatively impact your reef. I don't think RS Coral Pro is appropriate for you reef, Blue Bucket is better, but either way, this isn't the cause :)

I'd recommend just being consistent with water changes, and letting time fix everything else.

 

[Mr. Mojo Rising]

I would test daily for a 4-5 days, that is the best way to figure out the consumption. IMO for just a few corals, should be no need to dose anything

What kind of light have you got over the tank? Lighting IMO is 80% of it with corals, so if the corals are just surviving but not growing or thriving, I would start there.

 

[Randy Holmes-Farley Verified Community Expert]

I agree that you need to measure alk to see what’s happening.

 

[exnisstech]

I like to use a salt that mixes close to what my target is. Ie I target 8.5 dkH and use IO purple which mixes around 9 dkH

 

[bkayereefs]

I would test daily for a 4-5 days, that is the best way to figure out the consumption. IMO for just a few corals, should be no need to dose anything

What kind of light have you got over the tank? Lighting IMO is 80% of it with corals, so if the corals are just surviving but not growing or thriving, I would start there.

I have a have the AI Prime 16 over it with one of the presets from the professionals on the website

 

[bkayereefs]

Hi! I think this isn't a big issue. If your corals aren't thriving, I don't think it's your salt. Sure, you could use something with a record of success like Red Sea Blu Bucket (more closely mirrors the chemistry your tank is likely to fall into), but even with RS Coral Pro, 5 gallon changes aren't likely to negatively impact your reef. I don't think RS Coral Pro is appropriate for you reef, Blue Bucket is better, but either way, this isn't the cause :)

I'd recommend just being consistent with water changes, and letting time fix everything else.

I want to agree with this but the issue is I tested my alk today which is the day of water change, my alk was at a 7.3, my salt mix is rated at a 12dkh, that’s got to be shocking the corals weekly. So my need is to get the alk to like a 9 or 10 and keep it there I think

 

[Mr. Mojo Rising]

I have a have the AI Prime 16 over it with one of the presets from the professionals on the website

You can adjust the intensity on those presets. IMO your light should be around 85%-90%. I have AI Prime on a 15 gallon set at 85% for mostly mushrooms and zoa's. Depending on what intensity you have it set at now, this might be the reason your corals are just surviving.

 

[Randy Holmes-Farley Verified Community Expert]

I want to agree with this but the issue is I tested my alk today which is the day of water change, my alk was at a 7.3, my salt mix is rated at a 12dkh, that’s got to be shocking the corals weekly. So my need is to get the alk to like a 9 or 10 and keep it there I think

How large of a change are you doing? A 10% change will only boost the 7.3 dKH to 7.8 dKH, which is fine.

 

[bkayereefs]

I want to agree with this but the issue is I tested my alk today which is the day of water change, my alk was at a 7.3, my salt mix is rated at a 12dkh, that’s got to be shocking the corals weekly. So my need is to get the alk to like a 9 or 10 and keep it there I think

How large of a change are you doing? A 10% change will only boost the 7.3 dKH to 7.8 dKH, which is fine.

My tank is 20 gallons, with rock work I’d think it’s safe to assume there’s about 17 gallons of water in there and I do 5 gallons weekly

 

[Randy Holmes-Farley Verified Community Expert]

Ok, that’s a pretty large change to do at once, and matching all better may be desirable. :)

 

[bkayereefs]

Ok, that’s a pretty large change to do at once, and matching all better may be desirable. :)

Okay, so do you think the blue Red Sea salt would be better? The only issue with that is even with that switch the alk is still going to drop daily, further below with what the number is now. For example, right now I’m using purple coral pro mix, rated at 12dkh, if my alk in the tank itself is 8.3, (as of yesterday) that would mean it’s dropping fairly good. So wouldn’t the same thing happen with the Blue bucket rated at 10dkh? It may go to a 6.3, and then I’m back with the same issue where the water swapping is way higher. Sorry if that doesn’t make sense it’s hard for me to word lol. I’m just trying to see if anyone else with nano tanks doses for this issue

 

[Randy Holmes-Farley Verified Community Expert]

If you want to keep doing large changes, then yes, it would be better to use a lower alk mix. The other alternative is smaller changes, maybe more often to change the same amount.

Not sure where you get 10 dKH from. The Red Sea blue bucket is seemingly a fine choice. It claims to provide 7.5-8.5 dKH in advertisements.

 

[BryanM]

Hello fellow 20-gallon aquarists,

A quick suggestion: it’s time to learn a bit more about what your aquarium is actually consuming. The best way to do that is through consistent testing. Track your results and watch how the numbers change over time.

Try testing alkalinity daily for a week (or every couple of days if that’s more realistic), without doing any water changes during that period. For example, note where your alkalinity starts on Monday and where it ends on Sunday.

Once you establish how much your tank is naturally consuming, you’ll have real data to work with. Until then, I wouldn’t recommend dosing any alkalinity additives.

Once you have those results, I’d be happy to help further.

Also, here’s a couple photos of my 20-gallon for fun—and maybe a little street cred. LOL

Gimme that birdsnest!

 

[BryanM]

I want to agree with this but the issue is I tested my alk today which is the day of water change, my alk was at a 7.3, my salt mix is rated at a 12dkh, that’s got to be shocking the corals weekly. So my need is to get the alk to like a 9 or 10 and keep it there I think

Have you measured your salt when you mixed a fresh batch?

I started with that salt, but switched, I know people who run tanks successfully at 12dkh, but I settled in at 9 being my target.